Question

select the correct answer. which is a reservoir for nitrogen? a. lightning b. biomass c. nitrogen gas d. ammonium e. nitrogen - fixing bacteria

Explanation:

Nitrogen gas ($N_2$) makes up about 78% of the Earth's atmosphere and is the largest reservoir of nitrogen. Lightning can convert nitrogen gas to more reactive forms, biomass contains nitrogen - incorporated in organic compounds, ammonium is a reactive nitrogen compound, and nitrogen - fixing bacteria convert nitrogen gas to ammonia, but the main reservoir is nitrogen gas.

Answer:

C. nitrogen gas