Which of the following solutions will have pH close to 1.0

Options

A. `100 " mL of " M/10 HCl +100 " mL of "M/10 NaOH`
B. ` 55 " mL of " M/10 HCl + 45 " mL of " M/10 NaOH`
C. `10 " mL of " m/10 HCl + 90" mL of " M/10 NaOH`
D. ` 75" mL of "M/5 HCl + 25 " mL of " M/5 NaOH`

Answer

D

Explanation

M.eq of HCl = `1/5 xx 75 = 15`
M.eq of NaOH = `25 xx 1/5 = 5`
Total No. of eq. = `15 - 5 = 10`
Total volume = 100
Normality = `10/100 =1/10 , [H^(+)] = 10^(-1) M `