What are the differences between ammonia and nitrogen in terms of their chemical properties and environmental impact?

Ammonia is a compound made of nitrogen and hydrogen, while nitrogen is an element on its own. Ammonia is a gas with a pungent odor, while nitrogen is a colorless and odorless gas. In terms of environmental impact, ammonia can contribute to air and water pollution, while nitrogen is essential for plant growth but can also lead to water pollution if present in excess amounts.