Question

$0.1M$ $HCl$ and $0.1M$ $H_2{SO}_4$ each of volume $2mL$ are mixed and the volume is made up to $6mL$ by adding $2mL$ of $0.01N$ $NaCl$ solution. The pH of the resulting mixture is:

• A. $1.17$
• B. $1.0$
• C. $0.3$
• D. $\log 2-\log 3$

Answer 1

Answer: (B)

$1.0$

Total millimoles of $H^{+}$=$0.1\times 2+0.1\times 2\times 2=0.6mmoles$

So final concentration of $H^{+}$=$\frac{0.6}{6}=0.1M$

So $pH=-log\left(H^{+}\right)=1$