Question

Pure water does not conduct electricity because it

• A. has low boiling point
• B. is almost unionised
• C. is neutral
• D. is readily decomposed.

Answer 1

Answer: (B)

is almost unionised

Answer 2

For pure water $K _{ w }=\left[ H ^{+}\right]\left[ OH ^{-}\right]=10^{-14}$ $\therefore\left[ H ^{+}\right]=\left[ OH ^{-}\right]=10^{-7} M$ The concentration of ions is very less as water is almost unionised. $\therefore$ it does not conduct electricity.