Chlorine

How Is Chlorine Produced?

When you drop some hydrochloric acid onto potassium permanganate, chlorine will be formed.

Chlorine is a smelly, greenish-yellow gas, and hence its name: The Greek word chloros means yellow-green. Since chlorine is heavier than air, we were able to let the chlorine 'flow' into a vessel and observe how it looks and what it smells like.

How Can Chlorine Be Identified?

Since we wanted to demonstrate that Dan Klorix, a bleach, contains chlorine, we poured some into a test tube and added a few drops of sulphuric acid. The solution started to bubble, which indicated that chlorine was present in the solution - the bubbling was the chlorine gas! In addition, the liquid was white at the beginning and afterwards turned light yellow.

If a chemist needs table salt, he or she can buy it in a supermarket or produce it him or herself.

Table salt (NaCl) is made of sodium and chlorine atoms. Since we had already produced chlorine, as mentioned above, we were also able to produce table salt. For this purpose, our assistant, Christian, cut off a small piece of sodium and placed it into a kind of 'miniature tablespoon'. Afterwards, he heated the spoon with a Bunsen burner and placed it into the vessel filled with chlorine gas. The small piece of sodium started to bubble, which looked like boiling water. A small heap of white powder formed in the spoon, but we were not allowed to taste it, since it was not pure table salt. Next, we determined whether the white powder really was table salt: We poured it into a colourless solution of silver nitrate, which turned white as a result, as silver chloride had formed. We performed the same experiment with store-bought table salt. The colourless solution turned white as well.