Tolong dijawab nomor 28 / 29 (cara kerjanya)

1) NaOH —> Na+ + OH-
[NaOH] = 0,01 M mk [OH-] = 0,01 M

Mis kelarutan Mg(OH)2 dlm NaOH = a
Mg(OH)2 —> Mg2+ + 2OH-
Maka [Mg2+] = a

Ksp Mg(OH)2 = [Mg2+] [OH-]²
1,8.10⁻¹¹ = a (0,01)²
1,8.10⁻¹¹ = 10⁻⁴ a
a = 1,8.10⁻⁷ mol/L (D)

2) Ag2SO4 —> 2Ag+ + SO4²⁻
Mis kelarutan Ag2SO4 dlm air = a
Mk [Ag+] = 2a
dan [SO4²⁻] = a
Ksp Ag2SO4 = [Ag+]² [SO4²⁻]
3,2.10⁻⁵ = (2a)².a
3,2.10⁻⁵ = 4a³
a³ = 8.10⁻⁶
a = 2.10⁻² mol/L