$Assertion :$ Melting of solid causes no change in internal energy.
$Reason :$ Latent heat is the heat required to melt a unit mass of solid.
If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
If the Assertion is correct but Reason is incorrect.
If the Assertion is incorrect but the Reason is correct.
The latent heat of vaporization of a substance is always
Answer the following questions based on the $P$ - $T$ phase diagram of carbon dioxide:
$(a)$ At what temperature and pressure can the solid, liquid and vapour phases of $CO _{2}$ co-exist in equilibrium?
$(b)$ What is the effect of decrease of pressure on the fusion and boiling point of $CO _{2} ?$
$(c)$ What are the critical temperature and pressure for $CO _{2} ?$ What is their sıgnificance ?
$(d)$ Is $CO _{2}$ solid, liquid or gas at $(a)\;-70\,^{\circ} C$ under $1\; atm$, $( b )\;-60\,^{\circ} C$ under $10 \;atm,$ $(c)$ $15\,^{\circ} C$ under $56$ atm ?
Two different liquids of same mass are kept in two identical vessels, which are placed in a freezer that extracts heat from them at the same rate causing each liquid to transform into a solid. The schematic figure below shows that temperature $T$ versus time $t$ plot for the two materials. We denote the specific heat of materials in the liquid (solid) states to be $C_{L 1}$ $\left(C_{S 1}\right)$ and $C_{L 2}\left(C_{S 2}\right)$, respectively. Choose the correct option given below.
Triple point of water is
If liquefied oxygen at $1$ atmospheric pressure is heated from $50\, K$ to $300\, K$ by supplying heat at constant rate. The graph of temperature vs time will be