COMEDK 2025 Morning Shift

Choose the correct statement.

A non-volatile solute A weighing 60 g when dissolved in 212 g of the solvent Xylene reduces its vapour pressure to $60 \%$. What is the Molar mass of A in $\mathrm{g} / \mathrm{mol}$ ? [MM of xylene $=106 \mathrm{~g} / \mathrm{mol}$ ]

Choose the pair of elements $[(\mathrm{A})$ to $(\mathrm{F})]$ which:
(i) belong to the Chalcogen family
(ii) form monovalent oxides which give alkalies in aqueous solution
(iii) form stable monovalent anions
(A) $1 s^2 2 s^2 2 p^6 3 s^2 3 ...

The concentration and percentage purity of Oxalic acid can be determined by titration with $\mathrm{KMnO}_4$ in presence of dil. $\mathrm{H}_2 \mathrm{SO}_4$. Instead of dil. $\mathrm{H}_2 \mathrm{SO}_4$, dil HCl cannot be used because

Choose the correct statement.

Which one of the following options represents the decreasing order of oxidation number of the central atom in:
\(\mathrm{Cr}_2 \mathrm{O}_7^{2-}, \mathrm{Cr} \mathrm{O}_2^{-}, \mathrm{MnO}_4^{-}, \mathrm{BrO}_3^{-}\)

If X is a haloalkane with a single Chlorine atom per molecule and the percentage of Cl is 55 , what would be the number of Cl atoms present in 0.1 g of the haloalkane?
Atomic mass of $\mathrm{Cl}=35.5 \mathrm{~g} / \mathrm{mol}$

For a reaction $\mathrm{X}_2(\mathrm{l})+\mathrm{Y}_2(\mathrm{~g}) \leftrightharpoons 2 \mathrm{XY}(\mathrm{g})$, the $\Delta \mathrm{H}^0$ and $\Delta \mathrm{S}^0$ are $+29.3 \mathrm{~kJ} / \mathrm{mol}$ and $104.1 \mathrm{~J} \mathrm{~K}...

0.4 g of Propane burns completely at 300 K in a bomb calorimeter. The temperature of the calorimeter and surrounding water rises by $0.4^0 \mathrm{C}$. If the heat capacity of the calorimeter and contents is $24 \mathrm{~kJ} \mathrm{~K}^{-1...

Given that the standard enthalpy of combustion of $\mathrm{C}_{(\mathrm{S})}$ and $\mathrm{CS}_2(\mathrm{l})$ are -393.3 and $-1108.76 \mathrm{~kJ} / \mathrm{mol}$ respectively and the standard enthalpy of formation of $\mathrm{CS}_2$ is $1...