1. Write the balanced chemical equation for the complete combustion of methane gas.

2. Write the two step equations for the formation of sulfuric acid that results from the sulfur dioxide.

3. Atmospheric nitrogen combines with oxygen gas to form part nitric oxide (also known as nitrogen monoxide), a primary pollutant. Write the two step equations showing the formation of nitrogen oxide, the red-brown toxic gas found in smog.

4. Write the two step equations for the formation of ground level ozone.