Solubility of MOH2 in 0.1 M NaOH is Kspof MOH2=2×10-24M3
2×10-21 M
2×10-22 M
2×10-25 M
2×10-20 M
MOH2⇋M+2S+2OH-2S NaOH→Na+0.1 M+OH-0.1 M Ksp=M+2OH-2 Ksp=S2S+0.12; 'S' too small compared to 0.1M, it can be neglected; S=Ksp10-12=2×10-2410-2=2×10-22 M