Scienze e Viaggi

Experiments

We observed the behaviour of several substances exposed to the flame produced from a burner invented from Bunsen.

The cotton, burning, became black (coal) and then grey (cinders) and produced a smoke.

The wool over the flame produced a gaseous substance of a special smell and became cinders.

The third material was thread of nylon that we have put in a container that does not burn called boat; before the nylon is heated and subsequently it fuses. It emits an unpleasant but special smell.

The sugar (in the boat) over the flame does not burn but it is melted; it form caramel and holding it more to along on the flame it becomes black and hard. The smell is very pleasant, in early.

An elastic of natural rubber on the flame burns very fast and becomes cinders emitting a very unpleasant smell and black smoke.

The kitchen salt (in the boat) jumps and it becomes darker slightly . Late it is more dry but it has still the same taste and the same aspect.

The chalk of blackboard, put in the boat after to be reduced in dust, does not change aspect but emanates a very unpleasant smell.

These substances can be divided in two groups:

• organic substances (cotton, wool, nylon, sugar, natural rubber); these substances change in liquid or solid (coal) substances, with heating, then in cinders and gaseous substances, often, with a strong smell and black smoke.
• Inorganic substances (chalk, kitchen salt); these substances don't change with the heating that we used.