Question

What volume of $0.20$ $MHCl$ is required to exactly neutralize $40$ millilitres of $0.10$ $MNaOH$?

• A. $50$ ml
• B. $40$ ml
• C. $20$ ml
• D. $10$ ml
• E. $8$ ml

Answer 1

The correct option is C $20$ ml

$MV=M^{\prime }{V}^{\prime }$
$M$ is the molarity of $HCl$ (0.20 M).
$V$ is the volume of $HCl$.
$M^{\prime }$ is the molarity of $NaOH$ (0.10 M).
$V^{\prime }$ is the volume of $NaOH$ (40 ml).
$0.20\times V=0.10\times 40$
$V=20$ ml