Find the quantity of heat required to convert $40\; gm$ of ice at $-20^{\circ} C$ into water at $20^{\circ} C$. Given $L _{\text {ice }}$ $=0.336 \times 10^6 J / kg$.

specific heat of ice $=2100 \;J / kg - K$ sp heat of water= $4200\; J / kg - K$

Calculate the amount of heat (in calories) required to convert $5\,gm$ of ice at $0°C$ to steam at $100°C$

A thermally insulated vessel contains some water at $0^0C$. The vessel is connected to a vacuum pump to pump out water vapour. This results in some water getting frozen. It is given Latent heat of vaporization of water at $0^o C =21 × 10^5 J/kg$ and latent heat of freezing of water $= 3.36 × 10^5 J/kg$. The maximum percentage amount of water that will be solidified in this manner will be ...... $\%$

$10 \,gm$ of ice at $-20^{\circ} C$ is kept into a calorimeter containing $10 \,gm$ of water at $10^{\circ} C$. The specific heat of water is twice that of ice. When equilibrium is reached, the calorimeter will contain ..........

A geyser heats water flowing at a rate of $2.0 kg$ per minute from $30^{\circ} C$ to $70^{\circ} C$. If geyser operates on a gas burner, the rate of combustion of fuel will be $\dots \; g \min ^{-1}$

[Heat of combustion $=8 \times 10^{3} Jg ^{-1}$  Specific heat of water $=4.2 Jg ^{-1} \; { }^{\circ} C ^{-1}$ ]

A mass of material exists in its solid format its melting temperature $0\,^o  C$. The following processes then occur to the material

Process $-1$:An amount of thermal energy $Q$ is added to the material and $\frac{2}{3}$ of the material melts.

Process $-2$:An identical additional amountof thermal energy $Q$ is added to the materlal is now a liquid at $4\,^o C$

........ $^oC$ is the ratio of the latent heat of fusion to the specific heat of the liquid for this material.