The number of `H^(o+)` ions present in `1mL` of solution having `pH = 13` is

Explanation

`pH =13 therefore [H^+]=10^(-13)" mole per litre"`
Thus, mole of `H^+` in `1mL=(10^(-13))/(10^3)=10^(-16)`
no. of `H^+` in 1mL=mole of `1mL xx Av`. Constant. (Rule 4, chapter 1)
`=10^(-16) xx 6.022 xx 10^(23)`
`=6.022 xx 10^7`.