The saturation vapour pressure of water at $100°C$ is ........ $mm$ of mercury

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 ?

Latent heat of $1\,gm $ of steam is $536 \,cal/gm,$ then its value in $joule/kg$ is

Write a latent heat unit and dimensional formula. On what does the value of latent heat depend ?

The graph shown in the figure represent change in the temperature of $5 \,\,kg$ of a substance as it abosrbs heat at a constant rate of $42 \,\,kJ min^{-1}$. The latent heat of vapourazation of the substance is ......... $kJ \,kg^{-1}$

Explain the process of melting of ice with explanation of freezing, melting and melting point.