Ksp of Mg(OH)2 is 4.0×10-12.The number of moles of Mg2+ ions in one litre of its saturated solution in 0.1 M NaOH is??
Ksp = [Mg2+] [OH¯]2
Let the concentration of Mg2+ ions to form saturated solution be s mol/litre
4 x 10-12 = s x (0.1)2
s = 4 x 10-10 mol/litre
Volume of solution = 1 litre
Number of moles of Mg2+ = Molarity x Volume = 4 x 10-10 x 1 = 4 x 10-10 mol
Let the concentration of Mg2+ ions to form saturated solution be s mol/litre
4 x 10-12 = s x (0.1)2
s = 4 x 10-10 mol/litre
Volume of solution = 1 litre
Number of moles of Mg2+ = Molarity x Volume = 4 x 10-10 x 1 = 4 x 10-10 mol