Question

At 90∘C, pure water has [H3O+]=10−6m on the value of kw at this temperature is:

• A. (A) 10−12
• B. (B) 10−6
• C. (C) 1012
• D. (D) 106

Answer 1

Answer: (A)

(A) 10−12

Answer 2

Explanation:
Given: Concentration of H3O+=10−6 mol/LIonization reaction of H2O is : −H2O⇌H++OH−K=[H+][OH−][H2O]⇒K×[H2O]=[H+][OH−]∴Kw=[H+][OH−][H+]=[OH−]=10−6 mol/l(∵ it mentioned that it is purewater )Kw=[H+][OH−]=10−6×10−6=10−12Hence, the correct option is (A).