Q. At 90$℃$, pure water has $H_{3}O^{+}$ ion concentration of $10^{- 6}\ \frac{mol}{L^{- 1}}$. The $K_{w}\ at\ 90℃$ is
A) $10^{- 6}$
B) $10^{- 14}$
C) $10^{- 12}$
D) $10^{- 8}$
Explanation
(c)
$K_{w} = \left\lbrack H^{+} \right\rbrack\lbrack OH^{-}\rbrack$
$= \left( 10^{- 6} \right) \times \left( 10^{- 6} \right)$ $(\because\left\lbrack H^{+} \right\rbrack = \lbrack OH^{-}\rbrack)$
$= 10^{- 12}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.