A copper block of mass $2.5\; kg$ is heated in a furnace to a temperature of $500\,^{\circ} C$ and then placed on a large ice block. What is the maximum amount of ice (in $kg$) that can melt? (Specific heat of copper $=0.39\; J g ^{-1} K ^{-1}$ ;heat of fusion of water $=335\; J g ^{-1})$

If water at $0\,^oC$ kept in a container with an open mouth, is placed in a large evacuated chamber,

$Assertion :$ Melting of solid causes no change in internal energy.
$Reason :$ Latent heat is the heat required to melt a unit mass of solid.

The point on the pressure temperature phase diagram where all the phases co-exist is called

A liquid boils when its vapour pressure equals