Question

Which of the following solutions will have pH close to 1.0?  

(a) 100mL of (M/10)HCI + 100mL of (M/10) NaOH 

(b) 55mL of (M/10) HCl + 45mL of (M/10) NaOH 

(c) 10mL of (M/10) HCl + 90mL of (M/10) NaOH 

(d) 75mL of (M/5)HCI + 25mL of (M/5) NaOH

Answer 1

The correct option (d) 75mL of (M/5)HCI + 25mL of (M/5) NaOH

Explanation:

75mL of M/5HCl + 25mL of M/5 NaOH

Meq of HCl = 15 (∴ Mol. wt. and Eq. wt. of HCl or NaOH are same)

Meq of NaOH = 5

Hence, in solution 10meq of HCl are remained in 100mL solution.

So, concentration of HCl in mixture = 10/100M = M/10