The freezing point of `1` molal `NaCl` solution assuming `NaCl` to be `100%` dissociated in water is:

Options

A. `-1.86^(@)C`
B. `-3.72^(@)C`
C. `+1.86^(@)C`
D. `+3.72^(@)C`

Answer

B

Explanation

`DeltaT_(f)=1.86 xx 1 xx 2 = 3.72`,
`:.T_(f)=0-3.72 =-3.72^(@)C`
`NaCl` dissociates to give experimental molality `=1 xx 2 =2`