COMEDK 2025 Afternoon Shift

Lead storage battery contains $4.25 \mathrm{M} \mathrm{H}_2 \mathrm{SO}_4$ which has a density of $1.24 \mathrm{~g} / \mathrm{ml}$. Calculate the molality of aqueous solution of $\mathrm{H}_2 \mathrm{SO}_4$.

When $0.4 \mathrm{~g} \mathrm{CH}_3 \mathrm{COOH}$ is added to 40 g of Benzene to form a solution, the freezing point is depressed by $0.45^{\circ} \mathrm{C}$. If Acetic acid undergoes dimerisation in Benzene ( $\mathrm{K}_{\mathrm{f}}=5.1...

A dilute solution of $\mathrm{K}_2 \mathrm{HgI}_4$ reagent is $95 \%$ ionised. What would be the approximate value of its van't Hoff factor?

An aqueous solution which contains $42 \%$ by weight $(\mathrm{w} / \mathrm{W})$ of a volatile liquid "A" of molar mass of $140 \mathrm{~g} / \mathrm{mol}$, has a vapour pressure of 2141.4 mm of Hg at $37^{\circ} \mathrm{C}$. What is the va...

The first ionisation enthalpy of Al in $\mathrm{kJ} \mathrm{mol}^{-1}$ is:
[Given the first ionisation enthalpy of $\mathrm{Na}, \mathrm{Mg}$ and Si in $\mathrm{kJ} \mathrm{mol}^{-1}$ are 497,738 and 787 respectively]

The best method for the separation of $o$-nitrophenol and $p$-nitrophenol from their mixture is :

Given below are 2 statements: one Assertion and the other Reason. Which one of the following options is correct?
Assertion : Sulphur dioxide and Hydrogen peroxide can act as both oxidising and reducing agents but Nitric acid can act as only...

For the reaction $\mathrm{A}_2+\mathrm{B}_2 \cdots \cdots>2 \mathrm{AB}, \Delta \mathrm{H}_{\mathrm{f}}=-400 \mathrm{~kJ} / \mathrm{mol}$. The bond dissociation enthalpies of $\mathrm{A}_2$, $\mathrm{B}_2$ and AB are in the ratio $1: 0.75: ...

The Enthalpy of combustion of 1.0 mole of a reactive metal X at $27^{\circ} \mathrm{C}$ and 1.0 bar pressure to form a solid oxide ( XO ) is $-601.83 \mathrm{~kJ} / \mathrm{mol}$. The Internal energy change for this reaction is ___________ ...

For a hypothetical chemical reaction $\mathrm{A}_2+3 \mathrm{~B}_2+$ Heat $\cdots\rightarrow 2 \mathrm{AB}_3$, which one of the following combinations of state variables would support the spontaneity of the reaction at a particular temperat...