Fill in the blanks. Write the term that completes the statement.

1. ______________________ is a mixture of nitrogen, oxygen, and small amounts of other gas that surrounds the Earth and form its atmosphere.

2. ______________________ are solvents and used as refrigerants, foam blowing agents that cause the depletion of the atmospheric ozone layer.

3. ______________________ a form of oxygen which in a layer in the atmosphere ; screens out harmful ultraviolet rays from the sun.

4. ______________________ it is a transfer of heat by the circulation or movement of the heated parts of a liquid or gas.

5. ______________________ it is the most important greenhouse gas that is added to the atmosphere , which is produced by several natural processes and human activities.