In the reaction represented by the equation N2 + 3H2 => 2NH3, what is the mole ratio of nitrogen to ammonia?

This is the Haber Process.
Just from the balanced equation we can tell what is the mole ratio
N2 + 3H2  2NH3
1 mole of nitrogen has to react with 3 moles of hydrogen to form 2 moles of ammonia
Hence, answer is B
1 mole of nitrogen forms 2 moles of ammonia.
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