Question

How many moles of $R$ will be produced when $8$ mol of $P$ and $5$ mol of $Q$ are allowed to react according to the equation?
$2P+Q\to R$.

• A. 5
• B. 4
• C. 2
• D. 8

Answer 1

Answer: (B)

4

Let us consider the problem:

$2P+Q=R$,

Therefore,

Initial$:2P=8,Q=5,R=0$

Final$:P=4-4,Q=5-4\left(=1\right),C=4$

Hence $P$ is the limiting reactant

Because its moles $(=4)$ are less than those of $Q=5$

Therefore the correct answer is $4$.