Question

To a 4 litre of 0.2 M solution of NaOH, 2 litre of 0.5 M NaOH are added. The molarity of resulting solution is

• A. 0.9 M
• B. 0.3 M
• C. 1.8 M
• D. 0.18 M

Answer 1

Answer: (B)

0.3 M

Answer 2

Total moles of NaOH = $4 \times 0.2 + 2 \times 0.5$ = 0.8 $\times$ 1.0 = 1.8 Molarity =$\frac{1.8}{6}$ = 0.3 M