The depression in freezing point of `0.01 m` aqueous `CH_(3)CooH` solution is `0.02046^(@)`, `1 m` urea solution freezes at `-1.86^(@)C`. Assuming molality equal to molarity, `pH` of `CH_(3)COOH` solution is

Explanation

`DeltaT_(f)=K_(f)mxxi`
`i=(0.02046)/(0.01xx1.86)=1.1=1+x`
`:.x=0.1`
`[H^(+)]=C alpha=0.01xx0.1=10^(-3)`
`pH=3`