part-A
MX(s) --------------> M^+ (aq) + X^- (aq)
                             Â
s              Â
s
Ksp  = [M^+][X^-]
3.97*10^-36Â Â = s*s
s^2Â Â Â Â Â Â Â Â Â Â Â Â Â Â
= 3.97*10^-36
s              Â
= 2*10^-18 M
                  Â
= 2*10^-18 mole/L
part-B
     Ag2CrO4(s) ----------------->
2Ag^+ (aq) + CrO4^2- (aq)
                                                Â
2s                    Â
s
      Â
Ksp     = [Ag^+]^2[CrO4^2-]
       Â
1.12*10^-12Â Â = (2s)^2*s
        Â
4s^3Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â
= 1.12*10^-12
             Â
s             Â
= 6.54*10^-5M
             Â
s            Â
= 6.54*10^-5 mole/L
part-c
     Ni(OH)2(s) -------------->
Ni^2+ (aq) + 2OH^- (aq)
                                             Â
s                  Â
2s
        Â
Ksp   = [Ni^2+]OH^-]^2
       Â
5.48*10^-16Â Â = s*(2s)^2
           Â
4s^3Â Â Â Â Â Â Â Â Â Â Â Â Â
= 5.48*10^-16
                 Â
s            Â
= 5.15*10^-6M
                                 Â
= 5.15*10^-6 mole/L
         Â