A storage battery contains a solution of `H_(2)SO_(4) 38%` by weight. At this concentration, the Vant't Hoff factor is `2.50`. At what temperature will the battery contents freeze? `(K_(f)=1.86^(@) mol^(-1) kg)`

Explanation

Weight of `H_(2)SO_(4)` (solute), `w_(2)=38g" "therefore" Weight of water (solvent), "w_(1)=100-38 = 62g`
`therefore " Calculated value of "DeltaT_(f)=(1000K_(f)w_(2))/(w_(1)M_(2))=(1000xx1.86xx38)/(62xx98)=11.633^(@)`
`"van't Hoff factor, i "=("Observed "DeltaT_(f))/("Calculated "DeltaT_(f))`
`therefore" Freezing point "=273-29.08 = 243.92 K.`