Uploaded September 2019 | Updated September 2026, 2 weeks ago
You don’t need any chemicals for this experiment – you can do it right now!
Reagents and equipment: sugar (refined sugar works best), 500 mL boiling water, 6 glasses, pipettes, food coloring (4-5 different colors).
Distribute 500 mL boiling water evenly among 5 glasses. Don’t add any sugar to one of the glasses. Add to the rest of the glasses in turn: 2.5, 5, 7.5, and 10 sugar cubes. Add different colors of food coloring to each glass. Stir each solution thoroughly and let cool. Use separate pipettes to transfer each solution into another, single glass. Pour the solutions gently down the wall of the glass. Start with the solution with the most sugar (10 pieces) and continue in decreasing order. Voila, you’ve made a sugar rainbow! If the solutions mix too easily, try refrigerating them or increasing the difference in their sugar concentrations.
Density is the ratio of a body’s weight to the volume it occupies. If different masses of sugar are dissolved in two equal volumes of water, then the solution with more dissolved sugar will be denser. Moreover, if you arrange the solutions in order of decreasing density from the bottom up, they won't mix right away since no currents will form that could lead to the mixing of the solutions. It’s worth clarifying that diffusion between the layers does occur, so the sugar and dye molecules from the more concentrated (denser) solutions gradually diffuse into the less concentrated solutions, slowly equalizing their concentration throughout the volume of the vessel.
Safety precautions: perform this experiment only under adult supervision.
You don’t need any chemicals for this experiment – you can do it right now!
Reagents and equipment: sugar (refined sugar works best), 500 mL boiling water, 6 glasses, pipettes, food coloring (4-5 different colors).
Distribute 500 mL boiling water evenly among 5 glasses. Don’t add any sugar to one of the glasses. Add to the rest of the glasses in turn: 2.5, 5, 7.5, and 10 sugar cubes. Add different colors of food coloring to each glass. Stir each solution thoroughly and let cool. Use separate pipettes to transfer each solution into another, single glass. Pour the solutions gently down the wall of the glass. Start with the solution with the most sugar (10 pieces) and continue in decreasing order. Voila, you’ve made a sugar rainbow! If the solutions mix too easily, try refrigerating them or increasing the difference in their sugar concentrations.
Density is the ratio of a body’s weight to the volume it occupies. If different masses of sugar are dissolved in two equal volumes of water, then the solution with more dissolved sugar will be denser. Moreover, if you arrange the solutions in order of decreasing density from the bottom up, they won't mix right away since no currents will form that could lead to the mixing of the solutions. It’s worth clarifying that diffusion between the layers does occur, so the sugar and dye molecules from the more concentrated (denser) solutions gradually diffuse into the less concentrated solutions, slowly equalizing their concentration throughout the volume of the vessel.
Safety precautions: perform this experiment only under adult supervision.








![Chemical clock
Chemists are so punctual – they’ve even designed a chemical clock!
Hydrogen peroxide is a very active compound and can be both an oxidizer and a reducing agent. In this process, it reduces iodic acid to form molecular iodine and a so-called triiodide complex. This process can be simplified to the following chemical reactions:
HIO₃ + 3H₂O₂ → HI + 3O₂↑ + 3H₂O
5HI + HIO₃ → 3I₂ + 3H₂O
HI + I₂ → H[I₃]
Since oxygen is formed during the first reaction, we can observe the emergence of the gas. The iodine and triiodide complex turn the solution amber. But the solution immediately turns blue, since the starch molecules, which are very long and look like spirals, trap iodine molecules like a fishnet, forming a deep blue iodine-starch complex. Under the action of malonic acid, this complex is destroyed, since it reduces iodine molecules, while the solution itself becomes colorless:
C₃H₄O₄ + I₂ → C₃H₃O₄I + HI
The process repeats every few seconds, and the reaction period depends on the concentrations of the initial solutions. What is this if not a chemical clock?
Fun and safe experiments await you in the MEL Chemistry subscription!
Attention! All experiments are performed by professionals. Do not attempt. Chemical clock](https://i.ytimg.com/vi/ZhBNZV15uy0/mqdefault.jpg)

