Question

$300 g$ of $25 \% w / w$ solution of solute $A$ is mixed with $400 g$ of $40 \%( w / w )$ solution of another solute $B$. What is the w$/ w$ percentage of new mixture?

• A. 10.71% in A
• B. 35% in B
• C. 25% in A
• D. 40% in B

Answer 1

Answer: (A)

A: $300 g$ of $25 \% w / w$
$B : 400 g$ of $40 \% w / w$
$w / w \%$ of $A =\frac{25 \% \text { of } 300}{300+400}=\frac{75}{700} \times 100=10.71 \%$
$w / w \%$ of $B =\frac{40 \% \text { of } 400}{300+400} \times 100=22.85 \%$