Uploaded March 2021 | Updated September 2026, 2 weeks ago
Did you really think sulfur was that simple?
Sulfur molecules and crystals can have a variety of structures. Sulfur molecules can contain five atoms (S₅), eight atoms (S₈), or even more. In turn, the same molecules (for example, S₈), like construction toys, can be assembled in different ways: depending on how they are “stacked,” they’ll create solids with different structures. Solid sulfur powder consists of S₈ molecules that are folded in a special way, forming so-called rhombic sulfur. When the powder is heated, a yellow liquid of the same composition is formed. However, excess heat causes some of the molecules to polymerize, forming S₁₆, S₂₄, etc. and creating orange spots. A metal paper clip quickly absorbs the heat, and the sulfur crystallizes immediately. However, the molecules arrange themselves in a different way to how they started, forming so-called monoclinic sulfur. This creates a strong disc with a darker yellow hue than that of the powder. The molecules find this arrangement “inconvenient,” and rearrange over the course of several minutes (scientists call such structures metastable). This causes the disc to brighten noticeably and become so fragile that it is easy to break with three fingers!
Safe and cool chemical experiments await you in the MEL Chemistry subscription!
Attention! All experiments are performed by professionals. Do not attempt.
Did you really think sulfur was that simple?
Sulfur molecules and crystals can have a variety of structures. Sulfur molecules can contain five atoms (S₅), eight atoms (S₈), or even more. In turn, the same molecules (for example, S₈), like construction toys, can be assembled in different ways: depending on how they are “stacked,” they’ll create solids with different structures. Solid sulfur powder consists of S₈ molecules that are folded in a special way, forming so-called rhombic sulfur. When the powder is heated, a yellow liquid of the same composition is formed. However, excess heat causes some of the molecules to polymerize, forming S₁₆, S₂₄, etc. and creating orange spots. A metal paper clip quickly absorbs the heat, and the sulfur crystallizes immediately. However, the molecules arrange themselves in a different way to how they started, forming so-called monoclinic sulfur. This creates a strong disc with a darker yellow hue than that of the powder. The molecules find this arrangement “inconvenient,” and rearrange over the course of several minutes (scientists call such structures metastable). This causes the disc to brighten noticeably and become so fragile that it is easy to break with three fingers!
Safe and cool chemical experiments await you in the MEL Chemistry subscription!
Attention! All experiments are performed by professionals. Do not attempt.




![Chemical printing in 10 minutes
Chemical printing, or your favorite image on a postcard in 10 minutes
Equipment: sodium carbonate, citric acid, ammonium iron(III) sulfate, potassium hexacyanoferrate(III), beaker, cotton roll, watercolor paper, negative image, hair dryer.
Dissolve sodium carbonate, citric acid, ammonium iron(III) sulfate, and potassium hexacyanoferrate(III) in water to create a light-sensitive mixture. Use a cotton roll to apply this solution to a piece of watercolor paper, then cover the paper with a negative image and set the paper and negative under a lamp. After 10 minutes, remove the negative image and rinse the paper with water, then dry it with a hair dryer – you’ve made a cute winter postcard!
Under the influence of bright light, the iron(III) ions in the photosensitive mixture begin to actively enter an excited state. At the same time, they oxidize citric acid ions, resulting in the formation of a complex mixture of organic substances and iron(II) ions, with which potassium hexacyanoferrate(III) forms an insoluble blue compound:
Fe²⁺ + K₃[Fe(CN)₆] → KFe[Fe(CN)₆]↓ + K⁺
This compound is firmly fixed in the pores of the paper, so when rinsed with water, the blue pattern remains!
A similar experiment is included in the “Cyanotype” set from the MEL Chemistry subscription.
Warning: only under adult supervision. Chemical printing in 10 minutes](https://i.ytimg.com/vi/dcfAKVyYhtY/mqdefault.jpg)





