Question

The molarity of a solution obtained by mixing 800 m? of 0.5 M HCl with 200 mL of 1 M HCl will be

• A. 0.8M
• B. 0.6M
• C. 0.4 M
• D. 0.2M

Answer 1

Answer: (B)

${\underset{\text{Initial}}{M_1{V}_1+M_{2}V}}_2=\underset{\text{Final}}{M_3{V}_3}$
$V_3=V_1+V_2=800+200=1000mL$
$=0.5\times 800+1\times 200$
$=M_3\times 1000$
$M_3=\frac{600}{1000}=0.6M$