Answer
a. 3.0 moles of $H_2$
b. 0.30 mole of $N_2$
c. 0.93 mole of $NH_3$
Work Step by Step
a. Find the conversion factors, and calculate the amount of $ H_2 $ moles
$ N_2 $ and $ H_2 $: $$ \frac{ 1 \space mole \space N_2 }{ 3 \space moles \space H_2 } \space and \space \frac{ 3 \space moles \space H_2 }{ 1 \space mole \space N_2 }$$
$$ 1.0 \space mole \space N_2 \times \frac{ 3 \space moles \ H_2 }{ 1 \space mole \space N_2 } = 3.0 \space moles \space H_2 $$
b. Find the conversion factors, and calculate the amount of $ N_2 $ moles
$ NH_3 $ and $ N_2 $: $$ \frac{ 2 \space moles \space NH_3 }{ 1 \space mole \space N_2 } \space and \space \frac{ 1 \space mole \space N_2 }{ 2 \space moles \space NH_3 }$$
$$ 0.60 \space mole \space NH_3 \times \frac{ 1 \space mole \ N_2 }{ 2 \space moles \space NH_3 } = 0.30 \space mole \space N_2 $$
c. Find the conversion factors, and calculate the amount of $ NH_3 $ moles
$ H_2 $ and $ NH_3 $: $$ \frac{ 3 \space moles \space H_2 }{ 2 \space moles \space NH_3 } \space and \space \frac{ 2 \space moles \space NH_3 }{ 3 \space moles \space H_2 }$$
$$ 1.4 \space moles \space H_2 \times \frac{ 2 \space moles \ NH_3 }{ 3 \space moles \space H_2 } = 0.93 \space mole \space NH_3 $$
