Inedible lollypop

Grow a sugar lollypop

Difficulty:
Danger:
Duration:
5 days
Experiment's video preview

Safety

  • Put protective gloves on.

  • Conduct the experiment on the tray.

  • Observe safety precautions when working with boiling water.

  • Take protective gloves off before lighting the candle.

General safety rules
  • Do not allow chemicals to come into contact with the eyes or mouth.
  • Keep young children, animals and those not wearing eye protection away from the experimental area.
  • Store this experimental set out of reach of children under 12 years of age.
  • Clean all equipment after use.
  • Make sure that all containers are fully closed and properly stored after use.
  • Ensure that all empty containers are disposed of properly.
  • Do not use any equipment which has not been supplied with the set or recommended in the instructions for use.
  • Do not replace foodstuffs in original container. Dispose of immediately.
General first aid information
  • In case of eye contact: Wash out eye with plenty of water, holding eye open if necessary. Seek immediate medical advice.
  • If swallowed: Wash out mouth with water, drink some fresh water. Do not induce vomiting. Seek immediate medical advice.
  • In case of inhalation: Remove person to fresh air.
  • In case of skin contact and burns: Wash affected area with plenty of water for at least 10 minutes.
  • In case of doubt, seek medical advice without delay. Take the chemical and its container with you.
  • In case of injury always seek medical advice.
Advice for supervising adults
  • The incorrect use of chemicals can cause injury and damage to health. Only carry out those experiments which are listed in the instructions.
  • This experimental set is for use only by children over 12 years.
  • Because children’s abilities vary so much, even within age groups, supervising adults should exercise discretion as to which experiments are suitable and safe for them. The instructions should enable supervisors to assess any experiment to establish its suitability for a particular child.
  • The supervising adult should discuss the warnings and safety information with the child or children before commencing the experiments. Particular attention should be paid to the safe handling of acids, alkalis and flammable liquids.
  • The area surrounding the experiment should be kept clear of any obstructions and away from the storage of food. It should be well lit and ventilated and close to a water supply. A solid table with a heat resistant top should be provided
  • Substances in non-reclosable packaging should be used up (completely) during the course of one experiment, i.e. after opening the package.

FAQ and troubleshooting

Sugar crystals don’t grow on the splinter

If crystals are growing on the bottom of the beaker instead of on the splinter, then most probably, all the sugar seed crystals fell off the splinter and thus cannot act as crystallization centers for the splinter. If that is the case, repeat the step 2 of the instruction. This time, try dipping the splinter into the prepared sugar solution and then in granulated sugar. Make sure you let the splinter dry completely! After that, repeat the experiment starting from step 4.

Sugar crystals grow too slowly or don’t grow at all

If within 3−5 days there are almost no crystals formed on the splinter, try leaving the beaker with sugar in a warm place for a couple more days. It should help!

There is a sugar crust formed on the solution surface. What to do?

Such a sugar crust may form on top of the solution in a couple days since the experiment start. Don’t break it: doing so may damage the “lollypop”. Pour some more warm water on top: the crust should dissolve.

Step-by-step instructions

  1. Measure 8 full plastic vials of sugar into a plastic cup.

  2. Immerse a splinter into water, then—into sugar. Wait about 30 minutes until the sugar is dry.

  3. Fill the cup with water up to the sugar level.

  4. Fill the beaker with water up to the mark, as shown. Use caution when working with boiling water

  5. Place the plastic cup inside the beaker.

  6. Remove gloves before working with open flame! Put a candle on the solid fuel stove and ignite it.

  7. Place the flame diffuser onto the stove.

  8. Place the beaker on the flame diffuser. Stir the plastic cup contents until all the sugar dissolves.

  9. Thread the splinter through a filter paper, using its bare end.

  10. Remove the plastic cup from the beaker. Place the splinter inside the plastic cup, as shown. Leave the cup for 3–5 days at room temperature.

  11. Sugar crystals have grown on the splinter!
Graphical step-by-step instruction

Expected result

Sugar crystals grow on a splint. Thus, a real lollypop can be made at home!

Disposal

Dispose of the experiment residues along with regular household trash.

Scientific description

How exactly do we make a lollipop?

At the beginning of the experiment, we heat water. Simultaneously, it makes sugar actively dissolve in it, just like in hot tea. But in contrast to a hot tea, in our case, there is a lot of sugar in water. So much sugar that it would be impossible to dissolve it completely without heating the solution. It is therefore logical that during gradual water cooling, the solution “feels” overcrowded to all the dissolved sugar, and eventually it starts to gradually crystallize on a splinter.

Note that such a slow and gradual process is normally required to grow perfectly arranged crystals, without any shapeless formations. We can say that in many cases crystallization calls for a truly delicate attitude: certain temperature of a solution and of surrounding air; no shaking and even no lighting is allowed in some cases.

Why do crystals grow on a splinter?

Unlike in the other two experiment sets, sugar crystals growth occurs on a wood splinter, which already had a few sugar crystals stuck on it. Then, why do not these crystals grow somewhere else—for example, on the tube interior walls or even directly in the solution, as in the case with ammonium chloride?

As you know, like attracts like. For instance, such materials as wood, paper, cotton or cotton wool are based on the same material—cellulose. Cellulose falls into polysaccharide family: its molecules are very long and are composed of repeating blocks—glucose molecules. Similarly, sucrose molecule composition involves the same “building blocks.” As a result, sucrose successfully sticks to wood, especially if it has been pretreated with water. Thus, sucrose crystallization occurs on a splinter, as well as on those sugar crystals that have been already stuck on the splinter.

Show more details

The similarity of sucrose with moistened wood can be explained by an unusual, at first glance, interaction between molecules—a so-called hydrogen bonding. We will not go too far into details on the nature of hydrogen bonds, but let us discuss them briefly. In most hydrogen-containing compounds, H atoms are linked with so-called electronegative, or “electron-greedy,” atoms. The latter include fluorine F, chlorine Cl, bromine Br, sulfur S, oxygen O, nitrogen N, and sometimes even carbon C. Despite the fact that hydrogen atoms bind to other atoms via sharing their electrons (so that they “belong” to both atoms), in most cases these “greedy” atoms withdraw electrons from a hydrogen atom completely, so it feels, shall we say, deprived. As a result, such hydrogen atom carries a positive charge. And a “greedy” atom, in turn, carries a negative charge.

Two molecules may get strongly attracted to each other if a deprived hydrogen atom in one of them is facing exactly toward a sticking out “greedy” atom (for example, an oxygen atom) in another molecule. Since the principal actor here is a hydrogen atom that has found a delicate balance between the two “greedy” atoms, such interactions are called hydrogen bonds. If we recall the structure of a water molecule, we understand: wherever H2O molecules are close to each other, they tend to form numerous hydrogen bonds among themselves. It is hydrogen bonding that ultimately determines beautiful shapes of snowflakes and other unusual properties of water.

Now, let us get back to the tree and sucrose. Composition of a sucrose molecule contains many “sticking out” hydroxyl groups OH, which are attached to a carbon “backbone” of the molecule. They, too, can form hydrogen bonds: due to both a hydrogen atom, which carries a positive charge, and a “greedy” oxygen atom, which is negatively charged. As we mentioned earlier, the main component of wood is cellulose, which consists of repeating interlinked glucose molecules. The latter contains a whole set of OH-groups as well. Thus, all the “actors” — wood, water, and sugar — consist of particles that tend to form hydrogen bonds. That is why sugar easily sticks to a wet splinter, and then crystallization is triggered precisely on it.

Why does a lollipop grow so slowly?

This experiment is indeed very different from the rest in this set. In particular, the crystal growth is so slow that we have to wait a few days! What makes this experiment so special?

Sucrose has an important property: it can form so-called supersaturated solutions. To understand an intricate word “supersaturated,” let us conduct an imaginary experiment.

Imagine we are filling a glass with water. At some point, the glass is half-filled. Then, as water runs into the glass, it becomes filled. Moreover, if we are careful enough, we can overfill the glass with water, and it will form a “dome” on top. However, it is a very unstable state: even a slightest shake or vibration would disturb the balance, throwing the “dome” off center and turning the glass back to a simply filled state.

Interestingly, our solution can be compared with that glass. At first, when the amount of sugar in water is small, we “fill” the solution with sucrose molecules. At some point, the solution becomes saturated, or “full” of sucrose. However, we can manage to make it “full to the brim.” To do so, we only need to heat the solution containing an excessive amount of sugar, and then leave it to cool down slowly, just like in our experiment. Sugar is one of those substances that increase their solubility when heated. It means the higher the temperature, the higher the “capacity” of solution to “accommodate” sucrose molecules. The quantity of sucrose molecules in the solution remains the same as it is slowly cooling, but the solution “capacity” decreases. Hence, it brings the solution to a supersaturation state, making it “full to the brim.”

What does it mean for our experiment? It means that sucrose molecules are not in a hurry to leave the solution and form crystals. Therefore, this experiment requires more time to produce a beautiful lollipop.

Follow up

Edible lollipop

This experiment is called "inedible lollipop" because it is carried out using chemical equipment and utensils. But how to make a lollipop, which then can be eaten?

It's very simple, you only need to replace some of the items with their counterparts from everyday life. Instead of the beaker, take an ordinary heat-resistant glass, and instead of cups from the kit - regular disposable plastic cups, which can be purchased at any store. Finally, replace the splinter with a wooden skewer for fruit, a large toothpick or any other suitable object. The main criterion is that it must be made of wood - with plastic chopsticks the experiment will not work.

Now perform the experiment, according to the instructions and in a few days you will have your own lollipop! However, be careful when you eat it - sugar crystals grown this way usually have very sharp edges. To get rid of them, just lower the lollipop into water and hold it there a little bit.

Multicolored lollipops

How to make a colored lollipop? It is not difficult. Buy any water soluble food colorant and add some of it into the sugar solution before lowering the splinter therein. A colored lollipop will grow!

You can try to use even more available things- beet or blueberry juice, or other juices. By the way, try using juice instead of water to dissolve the sugar - what will happen?

That’s interesting!

Sugar: the history and production

Sugar as we know it today was first produced in ancient India, from sugar cane. Then, in antiquity, cane sugar became available to the ancient Rome due to the established Middle East trade routes. Egypt acted as a mediator there.

Sugar cane is a heat-loving plant, and climate in most of the Roman provinces was not suitable for its cultivation in Europe. In spite of this fact, sugar cane was adapted in southern Spain and Sicily, but unfortunately, this practice ceased due to the fall of the Roman Empire. However, after the establishment of the Arab rule in the Mediterranean in the ninth century AD, sugar cane cultivation rose again in Spain and Sicily, as well as in Egypt.

As time went by, some countries were replaced by others, but thermophilic properties of sugar cane remained unwaveringly constant on the background of historical processes. And with it remained constant the unavailability of sugar to European nations. Consequently, Europeans depended on the raw materials export for a long time, until the eighteenth century. Incidentally, after the discovery of Americas and its subsequent colonization, sugar cane began to be cultivated there as well.

In Europe, a solution to the problem of sugar production from domestic materials arose from using another plant—sugar beet. However, such production of sugar in Europe and Russia have only been established with the development of advanced chemical and technological processes, since sugar production from sugar beet is much more complicated than from sugarcane.

Regardless of raw materials, extraction of sugar from plants involves several steps:
1. Grinding and purification of an initial raw plant (in case of cane it is stalks, and for sugar beet it is their root-crops, which appear to be “storage roots” of the plant);
2. Heating the raw material with excess of water to draw sugar into solution;
3. Treatment of the resulting solution with various chemicals to remove all the other components but sugar from it (the major impurities are typically compounds of protein family);
4. Evaporating the resulting syrup (the last stage): water is removed, and sugar remains.

Note that a product of the last stage is brown sugar. Despite the fact that by general acceptance and because of its appearance it seems to be “dirtier” than “normal” refined white sugar, brown, or “unrefined,” sugar is more beneficial to health. Particularly, it contains B-group vitamins. As a result, for the past years, brown sugar sales have been actively increasing, and this product is reasonably called a “delicacy.”