Question

Consider the following reaction sequence:
$S_8\text{(s)}+8O_2\text{(g)}\to 8S{O}_2\text{(g)}$
$2S{O}_2\text{(g)}+O_2\text{(g)}\to 2S{O}_3\text{(g)}$
How many moles of $S{O}_3$ are produced from 10 moles of $S_8$?

• A. $10\text{mol}$
• B. $20\text{mol}$
• C. $40\text{mol}$
• D. $80\text{mol}$

Answer 1

The correct option is D $80\text{mol}$

According to the reaction,
1 mol of $S_8$ produces 8 mol of $S{O}_2$
therefore, 10 mol of $S_8$ produce $(8\times 10)=80\text{mol of}S{O}_2$
Similarly, 2 mol of $S{O}_2$ produce 2 mol of $S{O}_3$.
So, 80 mol $S{O}_2$ will produce 80 mol $S{O}_3$.