Chemistry 11 grade

Question

What is pH of 2.2x 10^-3 M of NaOH ?

What is pOH of 3.6 x10^-4M of H2SO4 ?

What is pH of 2.98 x10^-2M of HCl ?

Whay is pOH a 6.97 x 10^-5 M of KOH ?

Answer 1

1. What is pH of 2.2x 10^-3 M of NaOH ?
2. input into your calculator:
3. -
4. log
5. 2.2x10^3)
6. This gives you the pOH. Then round to 2 decimal points because there are 2 sig figs in your molarity (2.66 = pOH)
7. pH + pOH = 14.00
8. 14.00-2.66 = 11.34
9. 11.34= pH

Answer 2

Here's what you'll need to know to answer these.

pH = -log [H+]

pOH = -log [OH-]

pH + pOH = 14

2.2x10^-3 M NaOH ==> Na⁺ + OH^-

[OH-] = 2.2x10^-3

pOH = -log 2.2x10^-3 = 2.66

pH = 14 - 2.66

pH = 11.34

3.6x10^-4 M H₂SO₄ ==> H⁺ + HSO₄^-

[H⁺] = 3.6x10^-4 M counting only the 1st H+ that is donated. The 2nd H+ is for a more advanced class.

pH = -log 3.6x10^-4 = 3.44

pOH = 14 - 3.44

pH = 10.56

You should be able to do the next 2.