$17.0 \ g$ of $NH_3$ completely vaporizes at $-33.42^{\circ}C$ and $1 \ bar$ pressure, and the enthalpy change in the process is $23.4 \ kJ \ mol^{-1}$. The enthalpy change for the vaporization of $85 \ g$ of $NH_3$ under the same conditions is $..... \ kJ$.

$24 \ g$ of $Mg$ metal reacts with water. How many moles of $H_2$ will be liberated? ............. $mol$

Complete combustion of $3 \ g$ of ethane gives $x \times 10^{22}$ molecules of water. The value of $x$ is ......... (Round off to the Nearest Integer). [Use: $N_{A} = 6.023 \times 10^{23} ;$ Atomic masses in $u$ $C = 12.0, O = 16.0, H = 1.0$]

What will be the volume of $O_2$ gas at $STP$ which is obtained by thermal decomposition of $30.62 \ g$ $KClO_3$,with $80\%$ purity?

In what ratio by mass carbon dioxide $(CO_2)$ and nitrogen $(N_2)$ should be mixed so that the partial pressure exerted by each gas is the same?

When a mixture of $4.44 \, g$ of $CaCl_2$ and $NaCl$ is treated with a sodium carbonate solution,$Ca^{2+}$ ions precipitate as $CaCO_3$. Upon heating,this precipitate yields $0.56 \, g$ of $CaO$. Calculate the percentage of $NaCl$ in the original mixture. (Atomic mass of $Ca = 40 \, g/mol$)