Question

$200\, mL$ of $M / 5$ dibasic acid is mixed with $150 \,mL$ of $M / 2$ monoacid base. The $pH$ of the resulting solution is likely to be

• A. More than 7
• B. Less than 7
• C. Equal to 7
• D. Uncertain

Answer 1

Answer: (B)

$b(M V)_{A}=2 \times \frac{1}{5} \times 200=80$ millimoles

$a( MV )_{ B }=1 \times \frac{1}{2} \times 150=75$ millimoles

$\Rightarrow $ Acid dominates, $pH <\, 7$