Use the balanced equation to solve the problem \[ \mathrm{N}_{2}+3 \mathrm{H}_{2} \rightarrow 2 \mathrm{NH}_{3} \] \( 12.3 \mathrm{~g} \mathrm{NH}_{3} \) are made. How many liters of \( \mathrm{H}_{2} \) gas reacted at STP?

Step 1 ：\( \frac{12.3}{17.031} \mathrm{mol} \mathrm{NH}_{3}=0.7225 \mathrm{mol} \mathrm{NH}_{3} \)

Step 2 ：\( \frac{3 \mathrm{mol} \mathrm{H}_{2}}{2 \mathrm{mol} \mathrm{NH}_{3}} \times 0.7225 \mathrm{mol} \mathrm{NH}_{3}=1.0838 \mathrm{mol} \mathrm{H}_{2} \)

Step 3 ：\( 1.0838 \times 22.4=24.2767 \mathrm{L}\)