Air is compressed until a small piece of cotton is ignited. From a standpoint of thermodynamics what is Happening at a molecular level?

Energy cant be created of destroyed?

When air is compressed, its molecules are pushed closer together, causing an increase in pressure and a decrease in volume. At the molecular level, this compression results in an increase in the average kinetic energy of the air molecules. Essentially, the molecules are colliding more frequently and with higher energy.

Now, when a small piece of cotton is ignited in the compressed air, the added heat energy initiates a chemical reaction known as combustion. Combustion involves a rapid oxidation process where the cotton molecules react with oxygen from the air, releasing energy in the form of heat and light.

From the standpoint of thermodynamics, the key concept to understand is the conservation of energy. The law of conservation of energy states that energy cannot be created or destroyed, but it can be converted from one form to another. In this scenario, the energy present in the compressed air is being converted to heat and light energy through the combustion of the cotton.

So, to summarize, when air is compressed, its molecules gain energy due to increased kinetic motion. When a piece of cotton is ignited in the compressed air, the added heat initiates combustion, converting the energy from the compressed air into heat and light energy. The principle of energy conservation remains valid in this process.