2
a. [HO-] = 10^-14/[H3O+]
= 10^-14/10^-12 = 10^-2
pOH = -lg[HO-] = -lg(10^-2)
= -(-2)xlg10 = 2
stim ca pH + pOH = 14
=>pH = 14-pOH = 14-2 = 12
b. [H3O+] = 10^-pH
=> 10^-5 = 10^-pH
=> pH = 5
pH+pOH = 14 => pOH = 9
c. [H3O+] = 10^-pH
=> 10^-2 = 10^-pH
=> pH = 2
pH+pOH = 14 => pOH = 12
d. [H3O+] = 10^-pH
=> 10^-7 = 10^-pH
=> pH = 7
pH+pOH = 14 => pOH = 7
e. [H3O+] = 10^-14/[HO-]
= 10^-14/10^-11 = 10^-3
pH = -lg[H3O+] = -lg(10^-3)
= -(-3)xlg10 = 3
stim ca pH + pOH = 14
=>pOH = 14-pH = 14-3 = 11
f. [HO-] = 10^-pOH
=> 10^-4 = 10^-pOH
=> pOH = 4
pH+pOH = 14 => pH = 10
3.
a. pH = 7
=> [H3O+] = 10^-pH
=> [H3O+] = 10^-7 =>
[H3O+] = 10^-7 = [HO]
b. pOH = 3
=> [HO-] = 10^-pOH
=> [HO-] = 10^-3 =>
[HO-] = 10^-14/10^-3
=> [H3O+] = 10^-11
c. pH = 6
=> [H3O+] = 10^-pH
=> [H3O+] = 10^-6 =>
[H3O+] = 10^-6
=> [HO-] = 10^-14/10^-6 = 10^-8
d. pOH = 12
=> [HO-] = 10^-pOH
=> [HO-] = 10^-12 =>
[HO-] = 10^-14/10^-12
=> [H3O+] = 10^-2
