This question is about gases in the Earth's atmosphere.
The Earth's early atmosphere contained high levels of carbon dioxide. Today's atmosphere contains less than 0.04%0.04\%0.04% carbon dioxide. Explain why the amount of carbon dioxide in the atmosphere today has decreased from the early atmosphere.
The graph shows the concentration of nitrous oxide in the Earth's atmosphere from 1980 to 2020.
Describe the trend in the concentration of nitrous oxide in the Earth's atmosphere from 1980 to 2020.
Many scientists believe that greenhouse gases like nitrous oxide are contributing to global temperature rise.
Write down one human activity that releases nitrous oxide into the atmosphere.
Write down one way to reduce the amount of nitrous oxide released into the atmosphere from this activity.
Sulfur dioxide (SO2\text{SO}_2SO2) is a pollutant released during the combustion of fossil fuels containing sulfur impurities. Sulfur dioxide dissolves in water to form an acidic solution.
Suggest a value for the pH of this solution.
Describe one environmental problem caused by sulfur dioxide.