Question

At ${90}^{o}C$, pure water $\left[H_3{O}^{\oplus }\right]$ as ${10}^{-6}mol{L}^{-1}$ what is the value of $K_w$ at ${90}^{o}C$ ?

• A. ${10}^{-6}$
• B. ${10}^{-12}$
• C. ${10}^{-14}$
• D. ${10}^{-8}$

Answer 1

Answer: (B)

${10}^{-12}$

As we know, $K_w=\left[H^{+}\right]\left[O{H}^{-}\right]$

At ${90}^{o}C$, $\left[H^{+}\right]=\left[O{H}^{-}\right]={10}^{-6}$

So $K_w={10}^{-12}$

Hence,option B is correct.