JEE Main20209 Jan 2020Evening ShiftChemistryIonic EquilibriumActual
The solubility product of C r ( O H ) 3 at 298 K is 6.0 × 10 - 31 . The concentration of hydroxide ions in a saturated solution of C r O H 3 will be
Options
- A2.22 × 10 - 31 1 4
- B18 × 10 - 31 1 4
- C18 × 10 - 31 1 2
- D4.86 × 10 - 29 1 4
Correct answer
B. 18 × 10 - 31 1 4
Step-by-step solution
C r O H 3 → C r + 3 + 3 O - K s p = s . 3 S 3 ⇒ 6 × 10 - 31 = 27 . 3 s 4 ⇒ s = 6 27 × 10 - 31 1 / 4 O H - = 3 s = 3 × 6 27 × 10 - 31 14 = 18 × 10 - 31 1 / 4 M