$ 1 \text{ g} $ of ice is mixed with $ 1 \text{ g} $ of steam. At thermal equilibrium,the temperature of the mixture is (in $^{\circ} C$)

$Assertion :$ In the pressure-temperature $(P-T)$ phase diagram of water,the slope of the melting curve is found to be negative.
$Reason :$ Ice contracts on melting to water.

$A$ geyser heats water flowing at a rate of $2.0 \; kg$ per minute from $30^{\circ} C$ to $70^{\circ} C$. If the geyser operates on a gas burner,the rate of combustion of fuel will be $\dots \; g \min^{-1}$.
[Heat of combustion $= 8 \times 10^{3} \; J \cdot g^{-1}$,Specific heat of water $= 4.2 \; J \cdot g^{-1} \cdot {}^{\circ} C^{-1}$]

$22320 \ cal$ of heat is supplied to $100 \ g$ of ice at $0^{\circ} C$. If the latent heat of fusion of ice is $80 \ cal \ g^{-1}$ and latent heat of vaporization of water is $540 \ cal \ g^{-1}$, the final amount of water thus obtained and its temperature respectively are:

Match the following List-$I$ with List-$II$.

List-$I$	List-$II$
$A$. When ice melts into water	$I$. Volume increases
$B$. When water changes into steam	$II$. Volume decreases
$C$. Melting point of ice	$III$. Increases with increase of pressure
$D$. Boiling point of water	$IV$. Decreases with increase in pressure

The thermo $e.m.f.$ produced in a thermocouple is given by the equation $E = 40\theta - \frac{\theta^2}{20}$,where $\theta$ is the temperature difference between the two junctions. The neutral temperature is ............. $^oC$.