KspMg(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 :
4.0×10−10
1.0×10−4
2.0×10−6
8.0×10−6
[OH−]=[OH−]NaOH+[OH−]Mg(OH)2=0.1+2s≈0.1M(2X<<0.1)Ksp[Mg(OH)2]=[Mg2+][OH−]2=[Mg2+]×0.12=4.0×1012⇒[Mg2+]=4.0×10−12M
What is the hydrogen ion concentration of a solution whose pH is 3.70?