EAMCET Medical EAMCET Medical Solved Paper-2004

  • question_answer
    100 mL of 0.015 M HCl solution is mixed  "with 100 mL of 0.005 M HCl. What is the pH of the resultant solution?

    A)  2.5                                        

    B)  1.5

    C)  2                                            

    D)  1

    Correct Answer: C

    Solution :

                     For \[\text{HCl}\]molarity is equal to normality. So, the normality of the resulting mixture is calculated as \[\text{N}\,\text{= }\frac{{{N}_{1}}{{V}_{1}}+N{{}_{2}}{{V}_{2}}}{{{V}_{1}}+{{V}_{2}}}\] \[=\frac{0.015\times 100+0.005\times 100}{100+100}\] \[=\frac{1.5+0.5}{200}=\frac{2}{200}=\frac{1}{100}={{10}^{-2}}\] Normality of resulting mixture \[={{10}^{-2}}N\] Resulting solution is acidic in nature. So, this resulting normality represent the \[[{{H}^{+}}]\]concentration. Then,                    \[[{{H}^{+}}]={{10}^{-2}}\]                                 \[pH=-\log [{{H}^{+}}]\] \[=\log \frac{1}{[{{H}^{+}}]}=\log \frac{1}{{{10}^{-2}}}\] \[=\log {{10}^{2}}\] \[=2\log 10\] \[=2\]


You need to login to perform this action.
You will be redirected in 3 sec spinner