Question

The number of moles of hydrogen molecules required to produce 20 moles of ammonia by Haber's process is:

• A. 10
• B. 20
• C. 30
• D. 40

Answer 1

The correct option is C 30

Haber's process
$N_2$(g) + $3H_2$(g) $\rightleftharpoons$ $2N{H}_3$(g)

20 moles need to be produced
2 moles of $2N{H}_3$ gives 3 moles of $3H_2$
Hence, 20 moles of $N{H}_3$ gives $\frac{3\times 20}{2}$ = 30 moles of $H_2$