Question

1. what chemical has caused a breakdown in the ozone layer? why was this chemical used?

Explanation:

The chemical that has caused a breakdown in the ozone layer is chlorofluorocarbons (CFCs). CFCs were used because they are non - toxic, non - flammable, and stable under normal conditions. They were widely used in refrigerators, air conditioners, aerosol sprays, and as solvents and blowing agents in foam - making processes. Their stability made them suitable for these applications as they didn't react easily in the environments where they were used, but when they reached the stratosphere, they were broken down by UV radiation, releasing chlorine atoms that catalyzed the breakdown of ozone.

Answer:

The chemical causing ozone layer breakdown is chlorofluorocarbons (CFCs). CFCs were used due to being non - toxic, non - flammable, stable (suitable for refrigeration, aerosol sprays, foam - making, etc.), but in the stratosphere, UV breaks them down, releasing chlorine that destroys ozone.