10.
1.
[H3O+] = 10la-5 M
pH = -lg[10la-5] = 5, mediu acid
pOH = 14-5 = 9
=> [HO-] = 10la-pOH = 10la-9
2.
pH = 7, mediu neutru
=> [H+] = 10-pH = 10-7
=> [HO-] = 10la-14*10la-7 = 10la-7
=> pOH = lg[HO-] = 7
3.
[HO-] = 10la-4
=> pOH = -lg[HO-] = -lg(10la-4) = 4
=> pH = 14-4 = 10, mediu bazic
[H+] = 10la-14/[HO-] = 10la-14/10la-4
= 10la-10 M
11.
Ca = 10la-1 M
din teorie [H+] = Ca = 10-1 M
pH = -lg[Ca] = -lg(10la-1) = 1
