sugar crystallization experiment

Sugar Crystals

(water, sugar, string, pencil, container)

• Boil about 1 ½ cup (400 ml) water.
• Add about ¾ cup (200 ml) of sugar to the water, and stir the solution well.
• Pour the solution into the jar. Make sure that the jar you selected can withstand the temperature (a glass should work).
• Suspend the string from a pencil.
• Submerge the string in the solution.

The sugar crystals will grow slowly on the string over a period of several days.  If you want the string to hang straight in the jar, tie a weight to the bottom of the string.

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Home » Articles » STEM » STEM Science » How to make Sugar Crystals

How to make Sugar Crystals

Everyone tried to make homemade candy at some point. but have you ever tried to make rock candy on a stick they are not only delicious, but a great way to learn some chemistry. today we will show you how to grow your own sugar crystals. tasty science, article contents.

What are Crystals and how do they form?

Crystals are really special and unique material. They are solid material that forms from molecules that are arranged in exact and repeating patterns. Because of that, crystals can form all sorts of unique patterns – like a snowflake for an example. Each snowflake is unique and we will never find 2 exactly the same.

In the natural environment, crystals grow in one of three ways: from solution , from a melt, and from the vapor.

Crystals most commonly form from solution when liquids cool and start to harden. Like in our snowflake example. Molecules in liquid are getting together in an attempt to become stable. Also, liquid molecules are grouping in a repeating and uniform pattern which results in crystal formation. The process of crystal formation is called crystallization .

Most known crystals are rock crystals like diamonds, rubies, and emeralds and they form from a melt. They form from volcanoes when liquid magma cools. If magma cools slow enough, it will result in crystals forming. You can learn more about volcanoes in the article How to make a homemade Volcano .

Crystals can also form from evaporation . As the liquid evaporates slowly, it can form crystal formations. Salt crystals are the best example of crystallization when saltwater evaporates.

All crystals grow in a three-stage process : nucleation , growth , and termination .

• The first stage, called nucleation is when molecules are getting together and form a stable, subatomic structure in a repeating, uniform pattern.
• The second stage, called the growth stage is when more molecules are attracted and added to already formed subatomic structure. Additional molecules are added in a repeating, orderly manner. That is why crystals get their most recognizable feature – symmetry .
• The final stage, called termination is where the growth stops. Since there is no limit on how big crystal can grow, this stage is usually reached when there are no additional molecules that are attracted to the crystal and when there is no room for the crystal to expand.

As we already mentioned, there is no limit on how big a crystal can grow. The largest crystal ever found is beryl from Malakialina found in Madagascar. It is 18 meters long and more than 3 meters wide and weighs 380 tons. But crystal formation can take a long time. Even the growth rate of 2 millimeters per day means that hundreds of molecule layers must be laid down each second on the crystal surface. There is an enormous number of molecules required for crystal growth.

The science behind Sugar Crystals

How do we go from granulated sugar to sugar crystals? Well, sugar crystals form when molecules in sugar arrange themselves in a pattern and that happens when there is a lot of them in the small area. We call that process nucleation .

To achieve that, we need a solvent – water in our case, and a solute (granulated sugar). Dissolving solute in the solvent gives us a solution that can be more or less saturated. We want our solution to be saturated , so we will dissolve as much sugar as possible. The heat helps with the dissolving process, which means we can use even more sugar.

When we cool down our liquid it becomes supersaturated because now it holds the much greater concentration of sugar than water. In the supersaturated solution, we have more solute than solvent which means that the solution is unstable . Molecules collide with each other more frequently and that makes them stick together. With time, as more water evaporates, more and more molecules end up sticking together and we perceive that as a growth of our sugar crystal.

In the end, your rock candy is made by almost a quadrillion (10^15) molecules!

Materials needed for Sugar Crystals Experiment

• Funnel (optional)
• A couple of Jars
• Food Colors
• Wooden sticks
• Clothespins

Instructions for conducting an experiment

We have a video at the beginning of the article for a step by step instructions on how to conduct the sugar crystals experiment. Or you can read further for a detailed, step by step explanation of the whole process.

• Measure the sugar so the ratio is 1.5 cups of sugar on 1 cup of water.
• Add water to the pot and let it boil.
• When it boils, start pouring sugar. Let it dissolve completely before adding the next batch.
• Repeat until all sugar is gone. The solution should be thick at this point. Leave it to cool down for 15 minutes.
• Add some sugar on the plate. Take wooden sticks and soak it in the water at one end (that’s where the sugar crystals will form). After that rub that soaked part into the sugar. Leave it to dry for 30 minutes.
• Add sugary mixture into the jars. You can optionally add some food colors into jars so that crystals are colored.
• Now we need to put our sticks into the jars. We need to stabilize them so we will use clothespins. Connect two clothespins and pass the stick through the middle. Put the stick into the jar (the part which you coated in sugar earlier down) but don’t let it touch the bottom. Do this for all sticks/jars you have.
•  Leave the jars for 2 weeks. As time passes the crystals will grow.
• When you decide to take them out, first use something to break the upper layer (it will also be solid).
• Our homemade hard candy is done! Enjoy it! 🙂

What will you develop and learn making Sugar Crystals

• Chemistry Principles
• How to conduct an experiment, use the scientific method and perform observations
• Measuring and proportions
• How to make homemade hard candy and how to grow your own crystals

We hope you will enjoy this simple and fun kitchen experiment. It’s really tasty science! Sugar crystals are amazing to watch, so if you don’t want to eat them, you can use them as a decoration.

If you crave more kitchen experiments you can try How to make Homemade Playdough , How to make Homemade Plastic or Gummy Bear Osmosis Experiment .

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Wekiva Culinary

Magnet Academy of Culinary Arts at Wekiva High School

Working with Sugar: the Magic of Crystallization

What is sugar?

White granulated sugar = sucrose.

The white stuff we know as sugar is sucrose, a molecule composed of 12 atoms of carbon, 22 atoms of hydrogen, and 11 atoms of oxygen (C 12 H 22 O 11 ).

Like all compounds made from these three elements, sugar is a carbohydrate. It’s found naturally in most plants, but especially in sugarcane and sugar beets—hence their names.

Sucrose is a disaccharide – two simple sugars “stuck” together: fructose and glucose. At the molecular level, each grain of sugar consists of a small crystal made of an orderly arrangement of molecules.

If you look closely at dry sugar, you’ll notice it comes in little cubelike shapes. These are sugar crystals, orderly arrangements of sucrose molecules. 

What happens when you add sugar to water?

When you add granulated sugar to water, some of the sucrose molecules start separating because glucose and fructose molecules are attracted to the water molecules. Why? When a molecule of water and a molecule of sugar gets close to each other, the water disrupts the connection between the two simple sugars, the glucose and fructose molecules separate, and each of the simple sugars form temporary bonds with the water molecules around them.

In other words, each molecule of sucrose is like a couple going for a swim. When they get in the water, their relationship takes a break and they float away from each other (at least for a while).

How does sugar dissolve?

The dissolving process involves two steps: First, the water molecules bind to the sucrose molecules; and second, the water molecules pull the sucrose molecules away from the crystal and into the solution.

In general, only a certain amount of a solid can be dissolved in water at a given volume and temperature. If we add more than that amount, no more of that solid will dissolve. At this stage, we say that the solution is  saturated . The additional solid just falls to the bottom of the container.

This is why you can’t just keep adding sugar to water and expect all of it to dissolve. Once the solution hits the saturation point, there isn’t enough free water molecules to dissolve the new sugar you’ve added.

If you were able to see the molecules of sucrose and water, you would notice that, in the beginning, when you add a small amount of granulated sugar to the water, most of the sucrose molecules are leaving the sugar crystals, pulled away by the water molecules.

Here’s the important bit: you would also notice that some of the dissolved sucrose molecules are crystallizing, that is, not only are sucrose molecules LEAVING sugar crystals but sucrose molecules that had dissolved and were floating in the solution are REJOINING the sugar crystals. The reason is this: sucrose molecules are constantly moving in the solution, so nothing prevents some of them from binding again to sucrose molecules in the sugar crystals.

As long as the rate of dissolving is greater than the rate of crystallization, the sugar crystals remain dissolved in the water.

As we add more granulated sugar to the solution, the rate of dissolving decreases and the rate of crystallization increases , so at some point, both rates are equal. In other words, the number of sucrose molecules  leaving  the crystals is the same as the number of sucrose molecules  joining  the crystals. This is what happens when the solution is saturated. The crystals and the solution are in dynamic equilibrium, joining and leaving at the same pace. This means that the size of the crystals stays the same, even though the sucrose molecules are constantly trading places between the solution and the crystals

Past that point, if we add more sugar, the process of dissolving will continue, sure…. But it will be outpaced by the process of recrystallization.

It is impossible to dissolve more sugar than the quantity of liquid will support. The saturated ratio for a sugar solution is 1:2. In other words, you can create a saturated solution of one cup of water and two cups of sugar. More sugar than that, recrystallization occurs, and you no longer have a stable solution.

By the way – in cooking terms, a saturated sugar solution is called a “simple syrup.” Just thought you should know.

Le Châtlier’s Principle The crystallization process is explained by Le Châtelier’s principle, which states that a system that is shifted away from equilibrium acts to restore equilibrium by reacting in opposition to the shift. So an increase in temperature causes the system to decrease energy, in an attempt to bring the temperature down. Because the breakup of chemical bonds always absorbs energy, it cools the system down, so more sucrose molecules break apart and dissolve in the solution. What happens when the solution cools down? At this point, we see sugar crystals form. This is also explained by Le Châtelier’s principle: A decrease in temperature causes a system to generate energy, in an attempt to bring the temperature up. Because the formation of chemical bonds always releases energy, more sucrose molecules will join the crystal in an attempt to increase the temperature. This explains why crystals form when the temperature decreases.

How do you dissolve more sugar than the ratio of water to sugar will support? HEAT

As we’ve seen, when you add sugar to water, the sugar crystals dissolve and the sugar goes into solution. But you can’t dissolve an infinite amount of sugar into a fixed volume of water. When as much sugar has been dissolved into a solution as possible, the solution is said to be saturated. 

However, the saturation point is different at different temperatures. The higher the temperature, the more sugar that can be held in solution.

When you cook up a batch of candy, you cook sugar, water, and various other ingredients to extremely high temperatures. At these high temperatures, the sugar remains in solution, even though much of the water has boiled away. But when the candy is through cooking and begins to cool, there is more sugar in the solution than is normally possible. The solution is said to be supersaturated with sugar. 

Supersaturation is an unstable state. The reason the solution is unstable is it contains more solute (in this case, sugar) than can stay in solution—so as the temperature decreases, the sugar comes out of solution, forming crystals. The lower the temperature, the more molecules join the sugar crystals.

Cooking Sugar

Boiling a mixture of sugar and water does more than simply allow larger volumes of sucrose to dissolve in water. As the temperature of the sugar solution rises, water evaporates and leaves behind the sugar in its molten form. This creates a very concentrated sugar solution. Different sugar concentrations correspond to different types of candies (see the table below). In the case of hard candy, confectioners and professional candy-makers typically bring the boiling sugar solution to about 150°C (302°F) before removing it from the heat.  

Remember, supersaturated solutions are unstable, in the sense that any type of agitation, such as stirring or bumping, will trigger sugar crystallization: sucrose molecules will transition out of the molten liquid solution into a crystalline, solid state.

Grainy. Disgusting.

If you were melting sugar in a pan to make sugar art, you would heat the sugar very slowly, without stirring, until it becomes a clear liquid at about 338*F.

If you were melting sugar in a pan while making a flan – a custard with melted sugar on the bottom of the ramekin – you would heat the sugar to 351*F.

How to avoid gritty candy

The fact that sugar solidifies into crystals is extremely important in candy making. There are basically two categories of candies –  crystalline  (candies which contain crystals in their finished form, such as fudge and fondant), and  noncrystalline , or  amorphous (candies which do not contain crystals, such as lollipops, taffy, and caramels). Recipe ingredients and procedures for noncrystalline candies are specifically designed to prevent the formation of sugar crystals, because they give the resulting candy a grainy texture. 

METHOD 1: ADD ANOTHER TYPE OF SUGAR

One way to prevent the crystallization of sucrose in candy is to make sure that there are other types of sugar—usually, fructose and glucose—to get in the way. Large crystals of sucrose have a harder time forming when molecules of fructose and glucose are around. Crystals form something like Legos locking together, except that instead of Lego pieces, there are molecules. If some of the molecules are a different size and shape, they won’t fit together, and a crystal doesn’t form.

Another way is to add a nonsucrose sugar, such as corn syrup, which is mainly glucose. Some lollipop recipes use as much as 50% corn syrup; this is to prevent sugar crystals from ruining the texture. Corn syrup consists primarily of starch, which is nothing more than a string of sugar (glucose) molecules linked together. When heated, the starch breaks apart into its glucose components. These glucose molecules are smaller than sucrose and can impair crystallization by coming between the sucrose molecules, ultimately interfering with crystal formation.

In some recipes, invert sugar or honey may be added in lieu of corn syrup. Invert sugar and honey are both mixtures of glucose and fructose, which impede sucrose crystallization the same way corn syrup does.

METHOD 2: ADD SOME FAT

Fats in candy serve a similar purpose. Fatty ingredients such as butter help interfere with crystallization—again, by getting in the way of the sucrose molecules that are trying to lock together into crystals. Toffee owes its smooth texture and easy breakability to an absence of sugar crystals, thanks to a large amount of butter in the mix.

METHOD 3: ADD SOME ACID

If you don’t want to buy invert sugar, a simple way to prevent crystallization is to “invert” the sucrose by adding an acid to the recipe. Acids such as lemon juice or cream of tartar cause sucrose to break up (or invert) into its two simpler components, fructose and glucose. And if they are already broken up before cooking in water, there is a much smaller chance of crystallization.

METHOD 4: DO STIR THE SOLUTION AS IT COOLS; DON’T STIR AS IT COOKS

Supersaturation is an unstable state. The sugar molecules will begin to crystallize back into a solid at the least provocation. Stirring or jostling of any kind can cause the sugar to begin crystallizing. For this reason, it is important to avoid stirring the sugar as it cooks or while the temperature is raising to whatever candymaking stage you need.

When sugar granules stick to the sides of the pan, use a pastry brush dipped in a little water to wash them back down into the pan. Don’t stir and for god’s sake don’t use a whisk. Agitation at this stage can push the crystals back together and preemptively start the crystallization process. By the same token, you should use spotlessly clean utensils – a stainless steel spoon is recommended. The tiniest grain of dust or speck of fat will serve as a “seed” for sugar crystals to reform around.

If you MUST stir the sugar – swirl the pan gently, don’t stir it.

This is why leaving a popsicle stick in a glass of supersaturated sugar solution will form rock candy: the stick is providing the “seed” for crystals to form. Once the process begins, it will continue until much of the available dissolved sugar will leave the solution and joined the crystal structure.

ON THE OTHER HAND….

Once the mixture is cool, stir with a spoon or a spatula. A lot. Stirring prevents the sugar crystals that start to form from growing too big.

In general, a sugar crystal grows from a “crystal seed,” which is a clump of sucrose molecules, a speck of dust, or a gas bubble. Stirring causes the sucrose molecules to be pushed into one another, forming crystal seeds throughout the syrup. The resulting crystals will be smaller when more of the crystal seeds are present, because the sucrose molecules can join any of a larger number of crystal seeds.

When making fudge, once the solution has gotten cooled sufficiently, you start vigorously stirring or scraping it. It is important to let the fudge cool down FIRST because if you stir during the cooling phase, crystal seeds will probably form too soon and, as a result, may crystallize out of the solution, and the texture of the fudge would be grainy.

As you stir the fudge, many crystals form at once, and the stirring helps the sucrose molecules bind to one another and start forming small crystals. The main goal is to keep stirring continuously, which generates a larger number of small crystals. As the temperature decreases further, the sucrose molecules spread among the many crystal seeds and bind to any one of them, keeping the size of the crystals small. This creates the rich, melt-in-the mouth texture typical of fudge.

One syrup, many candies

Most candies are made from syrup yet their texture can vary substantially. Two factors play a key role: the length of time for crystals to grow, and the way the syrup is handled while it cools down.

In the case of rock candy, the syrup is left for several days, which provides plenty of time for the formation of large crystals. In the case of fudge, because the syrup is stirred continuously, a large number of small crystals is formed. When making glass candy, gummies, or marshmallows, the syrup is cooled down so quickly that no crystals can form at all.

Making candies is actually chemistry in action. You manipulate the size of sugar crystals—even if you cannot see them—to produce an array of textures. This skill has been developed over hundreds of years, before the science of candy-making was understood. But even then, this art form tells us something interesting about chemistry: It is not only the combination of ingredients that defines a product but also the way they are mixed together.

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Make Sugar Crystals

Introduction:.

Growing large, good quality crystals requires not only patience, care, and commitment, but also continual monitoring and assessment. The crystal growing project provides students with the opportunity to be actively involved in a long – term science project. The formation of a beautiful crystal at the conclusion of the project is extremely rewarding in itself. Additionally, the students learn much about crystals and their formation. Students are also required to write a short report on the project which further contributes to the learning process.

Making crystals is a business for many people. It is also the last step in production of many chemicals. The problem is that growing crystals is a slow process and we are trying to identify the conditions that can increase the rate of crystallization.

Dear This project guide contains information that you need in order to start your project. If you have any questions or need more support about this project, click on the “ Ask Question ” button on the top of this page to send me a message.

If you are new in doing science project, click on “ How to Start ” in the main page. There you will find helpful links that describe different types of science projects, scientific method, variables, hypothesis, graph, abstract and all other general basics that you need to know.

Project advisor

Information Gathering:

What is a crystal.

A crystal is a solid that consists of the various atoms, ions, or molecules being arranged in a uniform repeating pattern. This results in the material having a specific shape and color, and having other characteristic properties. Diamond (used in jewelry, and cutting tools) is an example of a crystal; it is made of pure carbon. Graphite (used in pencils and lubricants) is also a crystal made from carbon. Salt and sugar are also examples of crystals.

Recrystallization is a process that has been used to purify solid material by dissolving the solid (called a solute) in an appropriate liquid (called a solvent) and then having the material come out of solution in crystalline form. Depending upon conditions, one may obtain a mass of many small crystals or one large crystal.

More detailed information can be found on crystal types, shapes & sizes, light and color, how crystals form, and an encyclopedia review.

CRYSTAL TYPES

in terms of crystal systems and lattice types. There are 7 crystal systems:

1. triclinic 2. monoclinic 3. orthorhombic 4. tetragonal 5. trigonal 6. hexagonal 7. cubic

PHYSICAL AND CHEMICAL PROPERTIES OF SUGAR

chemical names : sucrose, saccharose, beta-D-Fructofuranosyl-alpha-D-glucopyranoside formula : C12H22O11 molar mass : 342.30 specific gravity : 1.587 melting point : 160 – 186 °C crystal class : monoclinic spenoidal

Question/ Purpose:

What do you want to find out? Write a statement that describes what you want to do. Use your observations and questions to write the statement. If you just want to make crystals, you do not need a question, variables and a hypothesis; however you may want to study on a specific question about making sugar crystals. This is a sample question:

How does the temperature affect the speed of crystallization?

Identify Variables:

When you think you know what variables may be involved, think about ways to change one at a time. If you change more than one at a time, you will not know what variable is causing your observation. Sometimes variables are linked and work together to cause something. At first, try to choose variables that you think act independently of each other. If you just want to make crystals, you do not need a question, variables and a hypothesis; however you may want to study on a specific question about making sugar crystals. This is how you may define variables:

Independent variable (also known as manipulated variable) is the temperature.

Dependent variable (also known as responding variable) is the amount of crystals formed in a certain period of time.

Constants are the amount of water, the amount of sugar, the size of the jar in each crystallization trial.

Hypothesis:

Based on your gathered information, make an educated guess about what types of things affect the system you are working with. Identifying variables is necessary before you can make a hypothesis. If you just want to make crystals, you do not need a question, variables and a hypothesis; however you may want to study on a specific question about making sugar crystals. This is a sample hypothesis:

Sugar solution forms crystals faster in cold temperatures.

Experiment Design:

Design an experiment to test each hypothesis. Make a step-by-step list of what you will do to answer each question. This list is called an experimental procedure. For an experiment to give answers you can trust, it must have a “control.” A control is an additional experimental trial or run. It is a separate experiment, done exactly like the others. The only difference is that no experimental variables are changed. A control is a neutral “reference point” for comparison that allows you to see what changing a variable does by comparing it to not changing anything. Dependable controls are sometimes very hard to develop. They can be the hardest part of a project. Without a control you cannot be sure that changing the variable causes your observations. A series of experiments that includes a control is called a “controlled experiment.”

Crystal Making Activity

Here is a procedure designed to produce many crystals using ordinary sugar.

HERE’S WHAT YOU DO

Pour the water into a saucepan and carefully heat it on the stove until the water boils, then turn off the heat.

Gradually add the sugar, a spoonful at a time, to the hot water and stir after each addition to dissolve. continue adding sugar gradually until no more will dissolve in the water. If necessary, heat the solution to make it clear.

Let the solution cool a bit and pour it into the tall jar. If the solution is too hot it might break the jar.

Cut a length of string which is about 6 mm (1/4 inch) shorter than the height of the jar. Attach a small weight (such as a piece of a clean rock) to one end of the string and tie the other end to the center of the pencil or narrow stick.

Let the solution cool (e.g. over night).

Moisten the string with water and rub some grains of sugar along the string. Let the string dry.

Slowly lower the string into the solution, making sure that the weight does not touch the bottom of the jar. Rest the pencil or stick across the rim.

Allow the solution and string to rest undisturbed for several days or weeks.

Watch what happens!

WHAT SHOULD HAPPEN?

You should see crystals growing in 5 to 15 days. If not, be patient; it might take longer.

The grains of sugar along the string act as ‘seeds’ on which crystals dissolved in the water are deposited as the sugar solution cools. The longer the string remains in the solution, the larger the crystals will grow.

After a while, the crystals will stop growing. To make them even bigger, carefully remove the crystals on the string. Pour the liquid into a sauce pan, carefully heat again, add more sugar, and repeat steps 2 and 3 above. Put your sugar string back into the solution.

All sugar crystals have the same characteristic shape regardless of size.

Please be patient. Remember, growing crystals takes time.

Experiment 1: How does the temperature affect the speed of crystallization?

1. Make a strong sugar solution (Boil 2 cups of water in a small sauce pan, add 4 cups of sugar, stir the mixture until the sugar is fully dissolved and you get a clear solution). 2. Transfer the solution to 3 identical plastic cups. Make sure all three cups have the same amount of sugar solution. 3. Cover all three cups with a plastic wrap 4. Place one of the cups in the refrigerator. 5. Keep one of the cups in room temperature. 6. Place the last cup in a warm place such as a warm oven (NOT HOT). 7. After one day, open all three cups. Empty the excess syrup and weigh the cups. 8. Which cup has the most crystal? Your results table may look like this:

Make a graph:

Use the above table and make a bar graph for visual presentation of your results. Make one vertical bar for each of the temperatures you test. Write the condition or temperature under each bar (For example you may write refrigerator under one of the bars)

The height of each bar represents the mass of crystals formed in that temperature.

Related Notes:

Seed crystals are very important in formation of sugar crystals. Seed crystals can be planted on the string or on a bamboo skewer, like sugar sticks. To prepare a bamboo skewer with crystal seeds, first insect the stick in sugar solution so it becomes sticky.

Remove excess liquid by rubbing the skewer against the container. Then insert the skewer in a pile of sugar. Small sugar crystals will stick to the skewer. Let it dry in a warm place.

After your sugar solution cools off, insect the seeded bamboo skewer in the solution. To hold the stick in place, you may use a piece of cardboard. Simply make a small hole in the center of a piece of cardboard and pass the skewer through the hole.

In a highly concentrated solution, you can see the growth of crystals as soon as you insert the seeded skewer in the solution. It will take about 7 days for crystals to become as large as commercially available sugar sticks.

Food coloring may be used to make sugar crystals in different colors.

Materials and Equipment:

HERE’s WHAT YOU NEED

• 1 cup water (distilled water works best)
• 1-1/2 to 2 cups granulated sugar
• 1 tall empty jar
• 1 Popsicle stick
• 1 paper clip
• fine string
• small saucepan
• Scale** ** You may already have a kitchen scale that can be used for your experiment. If you need need to buy one, make sure you buy a scale that measures in grams. Any scale with a capacity of 300 grams up to 500 grams will usually have the precision you need for your experiment.

Use this link to see s amples of scales available at WWW.KLK.COM online store.

Results of Experiment (Observation):

Experiments are often done in series. A series of experiments can be done by changing one variable a different amount each time. A series of experiments is made up of separate experimental “runs.” During each run you make a measurement of how much the variable affected the system under study. For each run, a different amount of change in the variable is used. This produces a different amount of response in the system. You measure this response, or record data, in a table for this purpose. This is considered “raw data” since it has not been processed or interpreted yet. When raw data gets processed mathematically, for example, it becomes results.

Calculations:

Keep track and record the amount of water and sugar that you use. Also record results in a time table.

Summery of Results:

Crystals need time to form and when they start growing, they appear everywhere, not just where we intend. As you have seen in the pictures, many crystals formed at the bottom and sides of the pan. We may find a nicely formed crystal among many others and use that as a seed for later experiments and get a larger crystal.

We hanged a string with a large knot at the bottom of that into the pan and expected the crystals grow on the knot. A small crystal ball formed on the knot, but many more crystals formed at the surface, sides and bottom of the pan. Picture in the left shows some of the side and surface crystals. Close observation

Conclusion:

Making sugar crystals is a fine task and needs accuracy and attention. Overheating the solution can cause decomposition and great discoloration. Too much sugar in solution can cause over saturation. Not enough sugar will cause under-saturation and in all these cases there will be no crystals.

The updated recipe that is now an attachment at the bottom of this project is made after some experiments and fine tuning the procedures.

Picture in the right shows a small crystal ball formed after 3 weeks in a saturated sugar solution. This crystal is formed on a knot at the bottom of the string.

Related Questions & Answers:

What you have learned may allow you to answer other questions. Many questions are related. Several new questions may have occurred to you while doing experiments. You may now be able to understand or verify things that you discovered when gathering information for the project. Questions lead to more questions, which lead to additional hypothesis that need to be tested.

Possible Errors:

If you did not observe anything different than what happened with your control, the variable you changed may not affect the system you are investigating. If you did not observe a consistent, reproducible trend in your series of experimental runs there may be experimental errors affecting your results. The first thing to check is how you are making your measurements. Is the measurement method questionable or unreliable? Maybe you are reading a scale incorrectly, or maybe the measuring instrument is working erratically.

If you determine that experimental errors are influencing your results, carefully rethink the design of your experiments. Review each step of the procedure to find sources of potential errors. If possible, have a scientist review the procedure with you. Sometimes the designer of an experiment can miss the obvious.

References:

Click here for more references. The history of sugar

Updated Recipe 1:

Making Rock Candy

Crystal Growing Experiment – Making Rock Candy

This is a nice little experiment for young scientists. Supplies: 600 grams (21 ounces) of sucrose (table sugar) 8 ounces of tap water a pot, beaker or saucepan to heat and mix the solution a candy thermometer (need to be able to measure 170°F) a spoon for mixing the solution heat source (stove) crystal growing container (glass or plastic which can tolerate boiling water)

Caution! Since this experiment involves heat, hot containers, and a hot sugar solution, there is the risk of burns. Use extreme caution to protect yourself from burns. Children should be supervised by an adult when performing this experiment because of the risk of burns.

Place 600 grams (21 ounces) of sugar into the pot for mixing and heating.

Pour 8 ounces (one cup) of water into the pot containing the sugar.

Stir the sugar and water until all the sugar is wet but not dissolved.

Heat the solution, stirring constantly. Place the candy thermometer into the solution to measure the temperature of the solution. Stir constantly until the solution is 170°F then remove the solution from the heat.

Continue to stir the solution as the solution cools to 125°F.

Pour the 125°F (HOT!) solution into the crystal growing vessel. Remember to use a vessel which will tolerate boiling water!

Allow the solution to cool to room temperature. Close/seal the container.

Crystal will grow in the container within 2 to 3 days. Maximum crystal growth will occur by 7 days. One can grow more and larger crystals by allowing water to evaporate from the solution (Crystallization by evaporation). Punch or cut holes in the top of the container or simply leave the lid off the container. It may take many weeks for the water to evaporate, therefore this method of crystal growth is much slower.

Additional Notes:

Adding more sugar will result in more crystals (likely smaller) and a more rapid appearance of the crystals.

Updated Recipe 2:

There are two simple basic methods to grow crystals from a sugar solution

The Evaporation Method The Slowly Cooling Method Using the evaporation method you simply let water to evaporate of your saturated solution to get crystals. Its quite simple but may take a long time.

Using the slowly cooling method you produce a hot saturated solution and let cool it down slowly to get the crystals. The catch is let it cool down slowly. As slower a solution cools down as bigger and finer the crystals will be. Fortunately the solubility of sugar rises greatly when the temperature goes up. The good thing is this method is quick you will get nice sized crystals within several hours to days.

The Evaporation Method

Dissolve per 100 grams of water 230 grams of sugar heat up the solution until it boils and gets clear. The solution may have a slight yellow hue. For heating up the solution use a cooking pot or a vessel made from heat resistant glass (Pyrex), as for example replacement jars for electric coffee machines. You may also use the microwave but of course only use vessels which are suitable for this (no metal or metal parts in microwave!). To grow the crystals you can use any kind of galas or plastic container with a wide open mouth. For example preservation glasses etc. You should produce at least about 500 ml of solution better around 1000 ml (or a quart). After the covered solution has cooled down so after two or three days there should be some sugar crystals at the bottom of the jar. If not throw in some little grains of sugar. Let the solution stay alone and covered for about a week. If you got no crystals on the bottom, yet even after throwing in some sugar grains your solution can not be saturated and won’t work. This may happen either because you made a mistake with the amounts of water and sugar used or your room temperature is well above 20 °C (app. 70 °F). To avoid mistakes in the amounts of water and sugar used, use an electronic kitchen scale which should have at least a resolution of 2 grams (better 1 gram) most can be switched from oz./lbs to metric, metric is easier to calculate. Also weigh the water as its much more accurate as measuring the volume.

Okay everything worked fine, there are some crystals at the bottom and the solution rested for a week. Now pour the solution in your final freshly cleaned growing vessel. You may filter but its not absolutely necessary and filtering the viscose solution may take for ever. Now you need a seed crystal, usually you will find at the bottom nicely sized sugar crystals already suitable for this purpose or you may use a bought candy sugar crystal (that’s cheating !). Dry up the crystal with some paper towel and fix it with a slip knot to a thread of “invisible sewing thread” which is a thin clear thread of nylon or use very thin fishing line. Don’t use regular threads made out of cotton etc. as they work like a wick and are easily visible in the ready crystal. Fix the thread to a piece of wood or a pencil for example so that the crystal suspends somehow above 2 – 3 cm (about one inch) the bottom of your growing vessel but well below the surface of the solution. Before doing that rinse the crystal on the thread shortly in cold water. The growing vessel must stay open to allow the water to evaporate but you may cover it with a thin paper towel (most paper towels are multi layer so you may split them) to prevent flies, wasps, dust etc. from falling into the solution. As the water evaporates your seed crystal will grow. This will not work if you are in a very humid climate or if your room temperature changes and goes up. As evaporation goes on there may grow additional crystals on the bottom of the vessel on the thread or on the sides. They grow on the cost of your desired main crystal. If so, pour the solution in a freshly cleaned other vessel rinse the crystal and the thread shortly in cold water (remove additional crystals which may have formed on the thread) and go on with evaporation.

The Slowly Cooling Method

If you produced the saturated solution for the evaporation method and found some crystals at the bottom you already used the slowly cooling method to produce crystals ! To get bigger and better ones you just have to add more sugar (larger “security gap”) and take care that the solution cools down very slowly. A good basic recipe is to add 230 to 300 grams of sugar to 100 grams of water, heat up until the solution boils and gets clear. Pour the solution in your final growing vessel and close it tightly. Take care that the the solution cools down very slowly by insulating it and also avoid any moving, shaking or vibration of the solution. You may give the crystals a better surface to grow, a matrix, if you put in a piece of rock, or have it suspended on a thread, or use a metal paper clip on a thread. It takes a few hours to days, depending on how much solution you take and how good your insulation is, until the solution has cooled down to room temperature and the crystals are ready. They main problems you may have with the slowly cooling method is that the solution does not cool down slowly enough, which results in small crystals or your solution has cooled down but there are no crystals at all ! What happened ? Supersaturation ! Your solution contains much more sugar as “allowed” since there have not formed any seed crystals spontaneously. If the solution is disturbed or you throw in some little sugar grains crystallization starts immediately. Since the growing velocity of sugar crystals is small, solutions are often slightly supersaturated when they have cooled down and so the crystals still grow a little while even if the temperature does not change anymore. So allow the crystals some extra time.

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Science Project

“Sugar crystals” experiment

How to make a sugar candy at home

Kids will love this ex­per­i­ment! It’s the most de­li­cious ex­per­i­ment for grow­ing crys­tals.

Safe­ty pre­cau­tions

Ob­serve safe­ty rules when work­ing with heat­ing de­vices.

Warn­ing! Only un­der adults su­per­vi­sion.

Reagents and equip­ment:

• bam­boo sticks;
• food col­or­ing (any kind);
• pa­per clamp;
• fry­ing pan.

Step-by-step in­struc­tions

Pre­pare the seed for crys­tals : add sug­ar and wa­ter to a fry­ing pan in the ra­tio of 10:1 and heat un­til the sug­ar dis­solves com­plete­ly. Pour the thick syrup into a bowl and dip the bam­boo sticks in it, then sprin­kle plen­ty of sug­ar on them, so it sticks. Leave to dry for a few hours.

Pre­pare the so­lu­tion to grow the crys­tals: add sug­ar and wa­ter to a saucepan in the ra­tio of 3:1 and heat slow­ly un­til the sug­ar dis­solves com­plete­ly. Leave the syrup on the hot plate to cool for 15-20 min­utes. Pour the cooled syrup into glass­es and add food col­or­ing .

Im­merse the sticks ver­ti­cal­ly in the cen­ter of each glass of syrup. They must not touch the bot­tom of the glass, or the walls! Cov­er with foil and leave in a dark place. Two weeks lat­er beau­ti­ful sug­ar crys­tals will grow on the sticks.

Dozens of experiments you can do at home

One of the most exciting and ambitious home-chemistry educational projects The Royal Society of Chemistry

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How to Make Sugar Crystals?

Are you looking for ways to make sugar crystals? If yes, we can help you teach how to make sugar crystals using the materials easily available at home. Kids would enjoy performing experiments to make sugar crystals. This will help them learn about the science behind the formation of sugar crystals. Conducting science experiments for kids enables them to observe and analyze the changes to come up with logical conclusions. This is one of the best DIY science project ideas for kids in the school curriculum. 

Contents 

• Easy Science Projects: How to Make Sugar Crystals?
• Aim of the Project
• Materials Required

Benefits of Learning How to Make Sugar Crystals

Frequently asked questions on how to make sugar crystals.

Can you make sugar crystals at home? Yes, it is an extremely easy and fun experiment for kids. It is better if kids carry out this experiment under the supervision of elders to get accurate results. You can conduct science experiments for toddlers , preschoolers, kindergarten and elementary school kids by unfolding the magic of making beautiful sugar crystals in front of their eyes. You can check out how to make sugar crystals mentioned in this article. 

Easy Science Projects: How to Make Sugar Crystals? 

Have your children eaten rock candies? How do you make them? You can prepare them from the crystallization process. When the sugar syrup freezes into ice, it becomes sugar crystals. You can teach kids the process of supersaturation and crystallization, the mechanism behind sugar crystal formation, by conducting this simple experiment effectively. For that, you need nothing but materials easily found at home. Read on to find out the sugar crystallization process from the experiment given below. 

Aim of the Project 

The aim of this project is to perform an experiment and observe how sugar crystals are formed using the materials available at home under the supervision of elders. 

Materials Required 

• A cup of boiling water 
• Two cups of sugar
• A glass 
• A stick 
• A piece of thread
• A few drops of food coloring liquid
• An aluminum foil 
• Take a cup of hot boiling water and pour it into a glass. 
• Add two cups of sugar to the boiling water. 
• Add a few drops of food coloring liquid. 
• Stir it well until it dissolves completely. 
• Take a stick and tie a piece of thread in the center. 
• Keep the stick on the glass so that the three-fourths of the thread is dipped inside the sugar syrup.
• Cover the glass with aluminum foil, leaving some air to cool down the sugar syrup. 
• Keep the glass for a week without disturbing it. 
• Observe and record the changes after a week.

In this experiment, kids observe that the sugar crystals are formed around the thread dipped inside the sugar syrup. When the temperature decreases, the sugar comes out of the solution to form crystals. The difference in the ratio of solute and solvent creates supersaturation of the solution. 

Also, explore how to separate salt and water .  

The benefits of learning the sugar crystallization process for kids are mentioned below. 

• It helps children understand the science behind the formation of sugar crystals. 
• It creates interest among children to perform experiments and observe how sugar crystals are made.
• It develops observational, problem-solving and analytical skills in children. 
• It motivates children to follow guidelines or procedures to perform experiments systematically. 
• It helps children score good marks in science subjects. 
• It teaches children to plan and execute experiments in an organized manner. 
• It nurtures creativity and curiosity among children to learn something new. 
• It enables children to observe and come up with logical conclusions for the experiment they are performing. 

To know more information, explore science games for kids , STEM activities for kids in the kids learning section at Osmo.

How to make sugar crystals?

You can conduct an experiment for kids to see the formation of sugar crystals using the material available at home by following the procedure on how to make sugar crystals mentioned in this article.

What are the benefits of learning how to make sugar crystals?

The benefits of learning how to make sugar crystals for kids are that it helps them learn the scientific concept behind the formation of crystals by performing simple experiments at home. Besides this, it develops curiosity to know the science behind crystal formation and observational skills at the same time.

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Science News Explores

Rock candy science 2: no such thing as too much sugar.

Here’s why you need so much sugar to make rock candy

Making rock candy at home takes a lot of sugar. How much? I did an experiment to find out.

ktaylorg/iStock/Getty Images Plus

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• Google Classroom

By Bethany Brookshire

April 30, 2020 at 6:30 am

This article is one of a series of  Experiments  meant to teach students about how science is done, from generating a hypothesis to designing an experiment to analyzing the results with statistics. You can repeat the steps here and compare your results — or use this as inspiration to design your own experiment.

Making rock candy at home requires just two ingredients — water and sugar. A lot of sugar, as I found out when I ran a rock candy experiment  in 2018 (and ran out of the sweet stuff). Most recipes recommend using about three times as much sugar as water. That’s so much, it seems like a waste. To see if I could get away with less, I ran another experiment.

Spoiler: Less sugar is not  the answer.

In my previous experiment, I showed that seed crystals are very important for creating rock candy. Putting a few grains of sugar on a stick or string promotes the formation of bigger crystals. This speeds up the candy-making.

I had calculated that to make enough rock candy for that experiment, I would need to fill 52 plastic cups with a sugar solution. But the candy recipe used more sugar than I was expecting and I quickly ran out. That’s because the recipe required one kilogram (8 cups) of sugar for every 300 grams (2.7 cups) of water. That’s a sugar-to-water ratio of 3:1. In the end, I had to run my experiment with only 18 plastic cups.

It all worked out in the end and I was able to test my hypothesis. But I wondered if I could have used less sugar and more water. To find out, another experiment was in order.

Super-saturated sugar

Making rock candy starts with dissolving sugar in water. The recipe’s ratio of sugar to water is so high, though, that the sugar won’t dissolve without some help. No matter how much I stir, there’s just too much sugar.

That changes when the water temperature increases. As water heats up, individual water molecules move faster and faster. Those speedy molecules can more easily break up the sugar crystals that had been dumped into the water. Soon, all the sugar dissolves in the water and the water turns clear.

This solution isn’t stable, however. It’s a super-saturated solution. The water contains more sugar than it can hold at room temperature. As the water cools, then, the sugar slowly precipitates out — becoming solid again. If the sugar crystals have something to attach to — such as a stick or piece of string with a little bit of sugar already on it — they will tend to attach there. Over time, enough sugar crystals cling together to make a chunk of rock candy.

But how super-saturated does my solution need to be to make rock candy? To figure this out, I’ll start with a statement that I can test — a hypothesis. My hypothesis is that using  a lower ratio of sugar to water in my solution will produce less rock candy than a mixture with a high-sugar concentration .

Cooking candy

To test this hypothesis, I made three batches of rock candy. The first batch is my control — the original rock candy recipe with a 3:1 ratio of sugar to water, a super-saturated solution. A second batch used a sugar-to water ratio of 1:1. That solution is saturated — the sugar goes into solution with stirring and maybe a little heat. The third group has a solution with a sugar-to-water ratio of 0.33:1. This solution is not saturated; the sugar dissolves into the water at room temperature.

I can’t make only one piece of rock candy for each test condition. I need to repeat my experiment and make enough rock candy to detect a difference between the three groups. For this experiment, that meant cooking up 12 batches of rock candy for each group.

I have made rock candy  for an experiment before. This time, I made a few changes:  

• Measure out and cut 36 clean pieces of string. Make sure there is enough string to tie around a stick above the cup, while still leaving string to dangle into the sugar solution.
• Dip one end of the string 12.7 centimeters (5 inches) into a cup of clean water, then roll it in a small pile of sugar. Set aside to dry.
• Set out 36 plastic or glass cups.
• For your 3:1 solution, mix 512 grams (4 cups) of water and 1.5 kilograms (12 cups) of sugar. I made two batches, which ended up using about 8 cups of water and 24 cups of sugar in total.
• For the 1:1 solution, add equal amounts of sugar and water to the pot and bring to a boil. So for 12 cups of water, you would need 12 cups of sugar.
• For the 0.33:1 solution, 15 cups of water and 5 cups of sugar should be plenty.  
• Once the solution is clear, add food coloring to get a desired color. I used red for my 3:1 solution, green for my 1:1 solution and blue for my 0.33:1 solution.
• If your solution is hot, you may want to wait a few minutes before pouring it into the cups. If the cups are thin, cheap plastic, the hot liquid might make them melt and sag. (This happened to me; my red cups were sad and saggy at the bottom.)
• Using a measuring cup, pour 300 milliliters (10 fluid ounces, a little more than a cup) of the solution into each cup. You may need to make another batch or two of each solution until you have enough to fill all 12 cups in each group.
• Weigh each string before you dip it into the solution. Use a scale to find the mass of each string in grams (each of mine weighed about one gram). Once you have noted the mass, dip the stick carefully into a cup of the sugar solution, then secure it in place. Make sure the string does not touch the bottom or sides of the cup. I tied each string to a wooden skewer placed across several cups.
• Put all the cups in a cool, dry place where they will not be disturbed.
• Wait. How long? You will start to see sugar crystals form after a day or so. But if you want candy to eat, you’ll want to wait at least five days.

At the end of the experiment, get out the scale again. Pull each string out of its cup, make sure it’s not dripping, and weigh it a second time. Should you eat it? Maybe not.

Have your data and eat it too?

To find out how much rock candy you made in each group, subtract the weight of each string at the beginning of the experiment from the weight of the candy-coated string. That will tell you how many grams of sugar crystals had grown.

At the end of my five-day experiment, I created a spreadsheet of my results, with each group getting its own column. At the bottom, I calculated the mean — the average crystal growth — for each group.

My super-saturated control group grew 10.5 grams of candy on average. The candy looked pink and tasty. But my other groups grew on average — zero grams of candy. They looked like soggy blue or green pieces of string. Some of the cups even grew mold. (Gross. Don’t eat those.)

Were the three groups different from each other? It certainly seemed like the super-saturated group was different. But to be sure, I needed to run some statistics — tests that will interpret my findings.

The first test I did was an analysis of variance , or ANOVA. This test is used to compare the means of three or more groups. There are free calculators that will run this test for you online. I used the one at Good Calculators .

This test gives you two outcomes, an F-stat and a p value. An F-stat is a number that tells you if three or more groups are different from each other. The higher the F-stat, the more likely it is that the groups are different from each other in some way. My F-stat was 42.8. That’s very large; there’s a big difference between those three groups.

The p value is a measure of probability. It measures how likely it is that I would find by accident alone a differences between my three groups that was at least as big as the one I report. A p value of less than 0.05 (or five percent) is considered by many scientists to be statistically “significant.” The p value I got from Good Calculators was so small it was reported as 0. There’s a 0 percent chance that I would see a difference this large by accident.

But these are just numbers that report a difference between the three groups. They don’t tell me where the difference is. Is it between the control group and the 0.33:1 group? The 1:1 group and the 0.33:1 group? Both? Neither? I have no idea.

To learn, I need to run another test. This test is called a post-hoc test — one that lets me further analyze my data. Post-hoc tests should only be used when you have a significant result to analyze.

There are many kinds of post-hoc tests. I used Tukey’s range test. It will compare all the means between all the groups. So it will compare the 3:1 ratio against the 1:1, then 3:1 to 0.33 to 1, and finally 1:1 to 0.33 to 1. For each, the Tukey’s range test gives a p value.

My Tukey’s range test showed that the 3:1 control group was significantly different from the 1:1 (a p value of 0.01, a one percent chance of a difference). The 3:1 group was also significantly different from the 0.33:1 (a p value of 0.01). But the 1:1 and 0.33:1 groups were not different from each other (which you would expect, since both of them averaged zero crystal growth). I made a graph to show my results.

This experiment seems pretty clear: If you want rock candy, you need a lot of sugar. The super-saturated solution is a must so that the sugar can crystallize out onto your string.

But there are always things that a scientist can do better in any study. For example, I had three groups with different amounts of sugar in the water. But another good control — a group where nothing changes — would be one with no sugar in the water at all.  The next time I want to make myself some candy, I’ve got another experiment to do.

Materials List

Granulated sugar (6 bags, $6.36 each) Grill skewers (pack of 100, $4.99) Clear plastic cups (pack of 100, $6.17) String ($2.84) Large pot (4 quarts, $11.99) Measuring cups ($7.46) Scotch tape ($1.99) Food coloring ($3.66) Roll of paper towels ($0.98) Nitrile or latex gloves ($4.24) Small digital scale ($11.85)

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Make rock candy

Follow FizzicsEd 150 Science Experiments:

You will need:

• 300g Of Sugar
• Saucepan or kettle with 500mL of water
• Wooden kebab stick or chopstick
• 2 Clothes pegs
• A metal spoon
• A place to leave the experiment setup away from ants
• Optional: food colouring

• Instruction

With adult help, carefully heat the water in a saucepan. You may want to add some food colouring as an optional extra too!

Stir in the sugar slowly, stirring constantly whilst the sugar dissolves. Keep adding sugar until you cannot dissolve the sugar crystals anymore. At this point just add a tiny bit more water and dissolve the leftover crystals as well.

Pour the saturated sugar solution carefully into a glass.

Using pegs to suspend a chopstick on the saturated sugar solution

Use two clothes pegs to suspend the wooden kebab stick or chopstick in the sugar solution without the stick touching the sides of the glass. Place the glass in space where ants cannot get at it (you might want to cover the experiment with a cloth).

Multiple rock candy experiments 

You may want to setup several experiments to see if the crystal formation differs with different amounts of sugar in the water.  It’s all about variable testing!

Rock candy beginning to grow on the chopstick

Observe the experiment over several days, taking note of when crystals start to form.

Rock candy crystals 

Run the experiment until you have grown the large sugar crystals along the stick (without the crystals touching the side of the glass).

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• How can we separate mixtures?
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• From chromatography to magnetism, join us to explore the variety of ways we can separate mixtures!

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Why Does This Happen?

You made a super-saturated solution of sugar and water! The sugar crystals could only stay dissolved whilst the water was hot. Cooling the solution down made it  super-saturated , which is unstable. As the water cooled down, less of the sugar crystals could remain in the water and so they began to settle out onto the kebab stick, which effectively acted as a seeding crystal. The sugar was more likely to settle on the kebab stick rather than the glass as the kebab stick has a rougher surface. This rough surface gives plenty of microscopic nucleation points for the molecules of sugar to settle. Over time, more and more of the sugar continued to settle out of the solution onto the kebab stick and so your crystals continued to grow!

Simply put, the longer it takes to form a crystal, the larger the crystal will be. This works whether you are talking about  crystal growing kits , making  liquid nitrogen ice-cream  or gemstones!

• Check out the link on crystals formed by volcanoes;  Indianapolis Childrens Museum
• Find out more about crystal seeding from this Hampton Research paper

Variables to test

More on variables here

• Try starting the experiment with hot vs. cold water… how much of a difference does this make?
• Vary the amount of sugar used in each experiment
• What happens when you use different liquids with sugar dissolved in it?
• Try different substrates for the sugar crystals to cling on too. Which work best?

Learn more!

From crystal growing to slimy science, we’ve got your kitchen chemistry covered! Get in touch with FizzicsEd to find out how we can work with your class.

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18 thoughts on “ Make rock candy ”

This was pretty helpful. I’m glad this could help me for my science fair project but maybe you guys should include a little bit more on how they actually form and start to clump to the dowel or skewer. Thanks!

Sure thing Amanda! It’s all about how rough the skewers are under a microscope. With super-saturated sugar solutions, the molecules of sugar more easily precipitate onto the rough surfaces of the kebab sticks than the smoother glass container. As the sugar molecules settle on the rough surfaces (also known as nucleation points), the crystallized sugar provides even more rough surfaces for the rest of the sugar to come out of solution. We’ve added a link into the post which takes to a detailed paper on seeding crystals too. Thanks for trying this science experiment, we’re glad that it helped your science fair project!

Does the sugar solution have to be thick for it to work?

Hi Ryan, great question! I want you to try several versions of thick vs thin (dense vs. less dense)… this way you’re doing real science and not just a trick 🙂

Once you know the answer, pop it in the chat below for everyone and you’ve helped everyone who reads your answer!

but how do you get it dense and less dense?

Love your question Ryan! Just change the different amount of the sugar syrup that you add to glasses of the same size and then top up with water to the same level. A bit of a mix and you’ve changed the density by diluting the sugar solution for each glass.

How long does it normally take? I’ve had it set up for almost 5 days now and there is little growth. Does it make a difference if we don’t boil the water?

Hi Caitlin! This has a lot to do with how saturated your solution is as well as how rough the substrate is that the crystals are settling on. Generally, we see crystals from between 1 & 2 weeks however the longer you leave it, the larger the crystals will be. You can try boiling vs not boiling the water too as a fir test, let us know how this goes!

Is it edible ?

Absolutely!

can we use brown sugar with it still working?

Sure thing! Although you’ll find that the rock candy will be darker in colour. Let us know how you go 🙂

So my name is Charlie (Charlotte) how many drops of food colouring do I put in?

Hi Charlie, this is dependent on how dark you would like the rock candy to be. Generally you only need a few drops 🙂

can we use honey if we don’t have 300g of sugar?

We’d love to know how you go!

My name is Lij (Elijah), how many drops do I have to put in then?

Hi Lij, try different drops in different tests and see the difference! Here’s more about variable testing here

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Fizzics Education curated a thoughtful and hands-on experience for the children, incorporating practical, skill-based learning activities and followed by a science presentation at the end of the event involving liquid nitrogen. This was delivered safely and effectively, capturing both the children and the parents for the duration of the presentation.

Fizzics Education ran a show today at our school and it was wonderful. He was a great facilitator and the show was age appropriate and well done.

I just wanted to pass on how much the staff and students really enjoyed it and how perfect it was to launch our science week activities. The students were enthralled, educated and entertained – a perfect trifecta!

Thanks so much for presenting at our school on Monday. Our students enjoyed the show.

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Sugar Crystals under the Microscope Preparation and Observations

Introduction.

In this post, we are going to observe the appearance of sugar crystals under the microscope. To get the best of this exploration, the compound microscope and the stereomicroscopes are used but the stereomicroscope offers the best result because of the stereoscopic or 3-Dimensional appearance of the sugar crystal lattice.

Using a Compound Microscope

Using the stereo microscope, sugar crystals observations.

With the stereo-microscope, there’s more in-depth focusing of the entire crystal structure as the microscope is better adapted for 3-dimensional viewing otherwise known as depth perception. The crystals appear like hexagonal pillars that have fallen over at one side and somehow flat on the surface.

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