Question

Heat needed to convert $1$ kilogram ice at $0^\circ C$ to steam at $100^\circ C$ is (in $Kcal$ ):-

Answer 1

Heat required to melt $1kg$ ice into water at $0^\circ C=80kcal.$ Heat required to raise temperature of $1kg$ water from $0^\circ C$ to $100^\circ C$ .
$=m S \cdot \Delta t=(1 \quad kg ) \times\left(1 kcal \quad kg ^{-1} \quad{ }^{\circ} C \right) \times(100-0)$
$=100 kcal$
Heat required to convert $1kg$ boiling water into steam at $100^\circ C$
$=mL=1kg\times 540kcalg^{- 1}=540kcal$
Thus, total heat required to convert $1kg$ of ice at
$0^\circ C$ into steam at $100^\circ C$
$=80+100+540=720kcal$