Question

**Chem 12 Question**


I know [H3O +]= [OH-] in neutral water

Considering the water is neutral (PH=7.000) ,Is it possible to add more acid to create a shift to the right to increase the concentration of [H3O+] and decrease the [OH-]?

Ex. HCl + H20 --> H3O+ + cl-

Answer 1

Alright, let's say if we add more acid right? H3O+

Answer 2

[H3O+][OH-] are equal right? if we put in more acid. the acid is going to react with the OH
so the OH- which is the base is going to pull off protons from the acid. what happens is we're going to have less OH which means that [OH-] goes down.

Answer 3

ok I get what you are saying. Is it also because of this?

Kw= [H3O+][OH-]

[OH-]= Kw/[H3O+]

If we add more HCl , since it is strong acid. The [H30+] = [HCl], so more H30+. Therefore, the higher the value of H3O+ concentration at bottom. The lower the value of OH- concentration.

Am I right?

Answer 4

Yes, @korosh23 in fact that's probably a better way to explain it.

remember Kw [H+][OH-] = 1x10^-14 at 25 C

so if we increase the concentration of H+ since we know that 1x10^-14 is a constant, the concentration of [OH] must go down.

Answer 5

Perfect. Thank you.