Although the air is about 78% nitrogen gas, most plants cannot use it directly because:

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Question

Although the air is about 78% nitrogen gas, most plants cannot use it directly because:

Accepted Answer

Nitrogen gas is unreactive and must be converted into nitrates first — Nitrogen gas (N₂) is very unreactive; plants take up nitrogen as nitrate ions from the soil, not as nitrogen gas.

Answer

Plants do not need nitrogen

Answer

There is too little of it

Answer

It is too heavy

Answer

Nitrogen gas is unreactive and must be converted into nitrates first

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