Question

17. In 10 ml of pH = 4 HCl solution 990 ml of 0.2 M
NaCl solution is added the pH of resulting solution
will be
(1) pH = 5
(2) pH = 5.5
(3) pH = 6
(4) pH = 4​

Answer 1

Quantity of solution = 10 ml (Given)

ph of the solution = 4 (Given)

Quantity of Hcl solution = 990ml (Given)

moles of H+ = 10 ×  (0.1/1000)

= 10^-3

Volume of the solution = 10+ 990 = 1000

Concentration of H+= moles = H+/Total volume of solution

= 10^-3/1000 = 10^-6

pH =-log(H+) = -log(10^-6)

= 6

Therefore, the pH of resulting solution  will be 6.

Answer 2

Refer the attachment.... Hope it is helpful ❤️