Physical Chemistry PYQ — Page 14

The correct set of four quantum numbers for the valence electron of rubidium atom $(Z=37)$ is

Activation energy $\left(E_a\right)$ and rate constants $\left(k_1\right.$ and $\left.k_2\right)$ of a chemical reaction at two different temperatures $\left(T_1\right.$ and $\left.T_2\right)$ are related by

Which of the following compounds can be used as antifreeze in automobile radiators?

Vapour pressure of chloroform $\left(\mathrm{CHCl}_3\right)$ and dichloromethane $\left(\mathrm{CH}_2 \mathrm{Cl}_2\right)$ at $25^{\circ} \mathrm{C}$ are $200 \mathrm{~mm} \mathrm{Hg}$ and $415 \mathrm{~mm} \mathrm{Hg}$ respectively. Vapour pressure of the solution obtained by mixing $25.5 \mathrm{~g}$ of $\mathrm{CHCl}_3$ and $4 \mathrm{O} \mathrm{g}$ of $\mathrm{CH}_2 \mathrm{Cl}_2$ at the same temperature will be: [Molecular mass of $\mathrm{CHCl}_3=119.5 \mathrm{~g} / \mathrm{mol}$ and molecular mass of $\mathrm{CH}_2 \mathrm{Cl}_2=85 \mathrm{~g} / \mathrm{mol}$ ]

Identify the wrong statement in the following.

The orbital angular momentum of a p-electron is given as

Maximum number of electrons in a subshell with $l=3$ and $n=4$ is

Buffer solutions have constant acidity and alkalinity because

Given that the equilibrium constant for the reaction, $$ 2 \mathrm{SO}_2(g)+\mathrm{O}_2(g) \rightleftharpoons 2 \mathrm{SO}_3(g) $$ has a value of 278 at a particular temperature. What is the value of the equilibrium constant for the following reaction at the same temperature? $$ \mathrm{SO}_3(g) \rightleftharpoons \mathrm{SO}_2(g)+\frac{1}{2} \mathrm{O}_2(g) $$

The Gibbs' energy for the decomposition of $\mathrm{Al}_2 \mathrm{O}_3$ at $500^{\circ} \mathrm{C}$ is as follows $$ \begin{gathered} \frac{2}{3} \mathrm{Al}_2 \mathrm{O}_3 \longrightarrow \frac{4}{3} \mathrm{Al}+\mathrm{O}_2 ; \\ \Delta_r G=+960 \mathrm{~kJ} \mathrm{~mol}^{-1} \end{gathered} $$ The potential difference needed for the electrolytic reduction of aluminium oxide $\left(\mathrm{Al}_2 \mathrm{O}_3\right)$ at $500^{\circ} \mathrm{C}$ is at least

$\mathrm{pH}$ of a saturated solution of $\mathrm{Ba}(\mathrm{OH})_2$ is 12. The value of solubility product $K_{\text {sp }}$ of $\mathrm{Ba}(\mathrm{OH})_2$ is

The enthalpy of fusion of water is $1.435 \mathrm{kcal} / \mathrm{mol}$. The molar entropy change for the melting of ice at $0^{\circ} \mathrm{C}$ is

Equimolar solutions of the following substances were prepared separately. Which one of these will record the highest $\mathrm{pH}$ value?

By what factor does the average velocity of a gaseous molecule increase when the temperature (in Kelvin) is doubled?

Consider the following processes $\Delta H(\mathrm{~kJ} / \mathrm{mol})$ $\begin{array}{ll}1 / 2 A \rightarrow B & +150 \\ 3 B \rightarrow 2 C+D & -125 \\ E+A \rightarrow 2 D & +350\end{array}$ For $B+D \rightarrow E+2 C, \Delta H$ will be

The van't Hoff factor, $i$ for a compound which undergoes dissociation in one solvent and association in other solvent is respectively.

Which one of the following statements is not true?

Which one of the following statements for the order of a reaction is incorrect?

The electrode potentials for $\begin{aligned} & \mathrm{Cu}^{2+}(a q)+e^{-} \longrightarrow \mathrm{Cu}^{+}(a q) \\ & \text { and } \mathrm{Cu}^{+}(a q)+e^{-} \longrightarrow \mathrm{Cu}(s) \\ & \text { are }+0.15 \mathrm{~V} \text { and }+0.50 \mathrm{~V} \text { respectively. The value } \\ & \text { of } E_{\mathrm{Cu}^{2+} / \mathrm{Cu}}^{\circ} \text { will be } \end{aligned}$

Which of the following is correct option for free expansion of an ideal gas under adiabatic condition?

If $x$ is amount of adsorbate and $m$ is amount of adsorbent, which of the following relations is not related to adsorption process?

The value of $\Delta H$ for the raction $X_2(g)+4 Y_2(g)^{39} 2 X Y_4(g)$ is less than zero. Formation of $X Y_4(g)$ will be favoured at

The freezing point depression constant for water is $-1.86^{\circ} \mathrm{C} \mathrm{m}^{-1}$. If $5.00 \mathrm{~g} \mathrm{Na} \mathrm{SO}_4$ is dissolved in $45.0 \mathrm{~g} \mathrm{H}_2 \mathrm{O}$, the freezing point is changed by $-3.82^{\circ} \mathrm{C}$. Calculate the van't Hoff factor for $\mathrm{Na}_2 \mathrm{SO}_4$.

The total number of atomic orbitals in fourth energy level of an atom is