The balanced chemical equation for the synthesis of ammonia from nitrogen and hydrogen is:
\[ N_2 + 3H_2 \rightarrow 2NH_3 \]
From the equation, we can see that 1 mole of nitrogen gas (N2) reacts with 3 moles of hydrogen gas (H2) to produce 2 moles of ammonia (NH3).
Therefore, if 1 mole of nitrogen gas reacts with 3 moles of hydrogen gas, the amount of ammonia produced is:
2 moles of NH3.