Question

400 ml of `1/200` M H₂SO₄, 400 ml of `1/100` M HCl and 200 ml water are mixed together, pH of the resulting solution is ______.

Options

• 2.1

• 2.8

• 3

• 3.1

Answer 1

400 ml of `1/200` M H₂SO₄, 400 ml of `1/100` M HCl and 200 ml water are mixed together, pH of the resulting solution is 2.1.

Explanation:

Total Meq of H₂SO₄ = `1/200 xx 2 xx 400` = 4

Total Meq of HCl = `1/100 xx 400` = 4

Total Meq of acid = 8

Total volume = 400 + 400 + 200

Total volume = 1000 ml

`["H"^+] = 8/1000`

pH = `- log ["H"^+]` = 2.1