Answer :
Full Question:
An aqueous solution at 25 C has a OH- concentration of 2.5x10-4M . Calculate the H3O+ concentration. Be sure your answer has the correct number of significant digits.
Answer:
4×10−9M
Explanation:
From the question;
[OH−] = 2.5x10-4M
[H3O+] = ?
The relationship between both parameters is given as;
Kw = [H3O+] * [OH−]
where k self-ionization constant of water, Kw = 1×10−14, which has no units.
Upon solving for [H3O+];
[H3O+] = Kw / [OH−]
Kw = 1×10−14
[H3O+] = (1×10−14 ) / 2.5x10-4
[H3O+] = 0.4 * 10-10
[H3O+] = 4×10−9M