The solubility product of a sparingly soluble metal hydroxide M ( OH )2 at 298 K is 5 × 10-16 mol 3 d m-9. The pH value of its aqueous and saturated solution is

Question

The solubility product of a sparingly soluble metal hydroxide M ( OH )2 at 298 K is 5 × 10-16 mol 3 d m-9. The pH value of its aqueous and saturated solution is (A) 5 (B) 9 (C) 11.5 (D) 8.5

Tardigrade Admin · Accepted Answer

M(OH)2 rightharpoons undersetsM+ + underset2s2OH- Ks p=(s)(2 s)2=4 s3=5 × 10-16 ∴ s=√[3](5 × 10-6/4)=5 × 10-6 Conc. of O H-=2 × 5 × 10-6 =10-5 mol dm -3 p O H=- log [O H-] =- log 10-5=5 p H=14-p O H =14-5=9 .

Q. The solubility product of a sparingly soluble metal hydroxide M(OH)2​ at 298K is 5×10−16mol3dm−9. The pH value of its aqueous and saturated solution is

5

9

11.5

8.5

M(OH)2​⇋sM+​+2s2OH−​ Ksp​=(s)(2s)2=4s3=5×10−16 ∴s=345×10−6​​=5×10−6 Conc. of OH−=2×5×10−6 =10−5moldm−3 pOH=−log[OH−] =−log10−5=5 pH=14−pOH =14−5=9.

Q. The solubility product of a sparingly soluble metal hydroxide $M (O H)_{2}$ at $298 K$ is $5 \times 1 0^{- 16} m o l^{3} d m^{- 9}$ . The $p H$ value of its aqueous and saturated solution is