JEE Main Chemistry — Physical Chemistry previous year questions with solutions.
If \(A_2 B\) is \(30 \%\) ionised in an aqueous solution, then the value of van't Hoff factor (i) is ______ \(\times 10^{-1}\).
Consider the following reaction occurring in the blast furnace: $\mathrm{Fe}_3 \mathrm{O}_{4(\mathrm{~s})}+4 \mathrm{CO}_{(\mathrm{g})} \rightarrow 3 \mathrm{Fe}_{(\mathrm{l})}+4 \mathrm{CO}_{2(\mathrm{~g})}$ ' $x$ ' kg of iron is produced when $2.32 \times 10^3 \mathrm{~kg} \mathrm{Fe}_3 \mathrm{O}_4$ and $2.8 \times 10^2 \mathrm{~kg} \mathrm{CO}$ are brought together in the furnace. The value of ' $x$ ' is _____. (nearest integer) Given: molar mass of $\mathrm{Fe}_3 \mathrm{O}_4=232 \mathrm{~g} \mathrm{~mol}^{-1}$ molar mass of $\mathrm{CO}=28 \mathrm{~g} \mathrm{~mol}^{-1}$ molar mass of $\left.\mathrm{Fe}=56 \mathrm{~g} \mathrm{~mol}^{-1}\right\}$
 Two vessels A and B are connected via stopcock. The vessel A is filled with a gas at a certain pressure. The entire assembly is immersed in water and is allowed to come to thermal equilibrium with water. After opening the stopcock the gas from vessel A expands into vessel B and no change in temperature is observed in the thermometer. Which of the following statement is true?
0.1 mol of the following given antiviral compound \((\mathrm{P})\) will weigh ________ \(\times 10^{-1} \mathrm{~g}\)  (Given : molar mass in \(\mathrm{g} \mathrm{mol}^{-1} \mathrm{H}: 1, \mathrm{C}: 12, \mathrm{~N}: 14\), \(\mathrm{O}: 16, \mathrm{~F}: 19, \mathrm{I}: 127)\)
Among $10^{-9} \mathrm{~g}$ (each) of the following elements, which one will have the highest number of atoms? Element : $\mathrm{Pb}, \mathrm{Po}, \mathrm{Pr}$ and Pt
Given below are two statements : Statement (I) : Corrosion is an electrochemical phenomenon in which pure metal acts as an anode and impure metal as a cathode. Statement (II) : The rate of corrosion is more in alkaline medium than in acidic medium. In the light of the above statements, choose the correct answer from the options given below :
$X Y$ is the membrane / partition between two chambers 1 and 2 containing sugar solutions of concentration $c_1$ and $c_2\left(c_1 \gt c_2\right) \mathrm{mol} \mathrm{L}^{-1}$. For the reverse osmosis to take place identify the correct condition (Here $p_1$ and $p_2$ are pressures applied on chamber 1 and 2)  (A) Membrane/Partition; Cellophane, $\mathrm{p}_1 \gt \pi$ (B) Membrane/Partition ; Porous. $\mathrm{p}_2 \gt \pi$ (C) Membrane/Partition ; Parchment paper, $\mathrm{p}_1 \gt \pi$ (D) Membrane/Partition : Cellophane, $\mathrm{p}_2 \gt \pi$ Choose the correct answer from the option given below :
Given below are two statements : Statement (I) : NaCl is added to the ice at $0^{\circ} \mathrm{C}$, present in the ice cream box to prevent the melting of ice cream. Statement (II) : On addition of NaCl to ice at $0^{\circ} \mathrm{C}$, there is a depression in freezing point. In the light of the above statements, choose the correct answer from the options given below :
Assume a living cell with $0.9 \%(\omega / \omega)$ of glucose solution (aqueous). This cell is immersed in another solution having equal mole fraction of glucose and water. (Consider the data upto first decimal place only) The cell will :
Which of the following graph correctly represents the plots of \(\mathrm{K}_{\mathrm{H}}\) at 1 bar gases in water versus temperature?
40 mL of a mixture of $\mathrm{CH}_3 \mathrm{COOH}$ and HCl (aqueous solution) is titrated against 0.1 M NaOH solution conductometrically. Which of the following statement is correct? 
The standard reduction potential values of some of the p-block ions are given below. Predict the one with the strongest oxidising capacity.
Half life of zero order reaction $\mathrm{A} \rightarrow$ product is 1 hour, when initial concentration of reaction is $2.0 \mathrm{~mol} \mathrm{~L} \mathrm{~L}^{-1}$. The time required to decrease concentration of A from 0.50 to $0.25 \mathrm{~mol} \mathrm{~L}^{-1}$ is:
Consider the given data : (a) $\mathrm{HCl}(\mathrm{g})+10 \mathrm{H}_2 \mathrm{O}(\mathrm{l}) \rightarrow \mathrm{HCl}.10 \mathrm{H}_2 \mathrm{O}$ $\Delta \mathrm{H}=-69.01 \mathrm{~kJ} \mathrm{~mol}^{-1}$ (b) $\mathrm{HCl}(\mathrm{g})+40 \mathrm{H}_2 \mathrm{O}(\mathrm{l}) \rightarrow \mathrm{HCl}.40 \mathrm{H}_2 \mathrm{O}$ $\Delta \mathrm{H}=-72.79 \mathrm{~kJ} \mathrm{~mol}^{-1}$ Choose the correct statement :
In a multielectron atom, which of the following orbitals described by three quantum numbers will have same energy in absence of electric and magnetic fields? A. $\mathrm{n}=1, \mathrm{l}=0, \mathrm{~m}_1=0$ B. $\mathrm{n}=2, \mathrm{l}=0, \mathrm{~m}_1=0$ C. $\mathrm{n}=2, \mathrm{l}=1, \mathrm{~m}_1=1$ D. $\mathrm{n}=3, \mathrm{l}=2, \mathrm{~m}_1=1$ E. $\mathrm{n}=3, \mathrm{l}=2, \mathrm{~m}_1=0$ Choose the correct answer from the options given below:
Ice and water are placed in a closed container at a pressure of 1 atm and temperature 273.15 K . If pressure of the system is increased 2 times, keeping temperature constant, then identify correct observation from following
When 81.0 g of aluminium is allowed to react with 128.0 g of oxygen gas, the mass of aluminium oxide produced in grams is_______ - (Nearest integer) Given : Molar mass of Al is $27.0 \mathrm{~g} \mathrm{~mol}^{-1}$ Molar mass of O is $16.0 \mathrm{~g} \mathrm{~mol}^{-1}$
The hydrocarbon $(X)$ with molar mass $80 \mathrm{~g} \mathrm{~mol}^{-1}$ and $90 \%$ carbon has $\ldots\ldots$ degree of unsaturation.
Given below are two statements : Statement I : When a system containing ice in equilibrium with water (liquid) is heated, heat is absorbed by the system and there is no change in the temperature of the system until whole ice gets melted. Statement II : At melting point of ice, there is absorption of heat in order to overcome intermolecular forces of attraction within the molecules of water in ice and kinetic energy of molecules is not increased at melting point. In the light of the above statements, choose the correct answer from the options given below:
A person's wound was exposed to some bacteria and then bacteria growth started to happen at the same place. The wound was later treated with some antibacterial medicine and the rate of bacterial decay (r) was found to be proportional with the square of the existing number of bacteria at any instance. Which of the following set of graphs correctly represents the 'before' and 'after' situation of the application of the medicine? [Given : $\mathrm{N}=$ No. of bacteria, $\mathrm{t}=$ time, bacterial growth follows $I^{\text {st }}$ order kinetics.]
10 mL of 2 M NaOH solution is added to 20 mL of 1 M HCl solution kept in a beaker. Now, 10 mL of this mixture is poured into a volumetric flask of 100 mL containing 2 moles of HCl and made the volume upto the mark with distilled water. The solution in this flask is :
Match List-I with List-II $\begin{array}{|l|l|l|l|}\hline & \text{List-I} & & \text{List-II} \\ \hline \text{(A)} & \begin{array}{l} \text{Solution of} \\ \text{chloroform and} \\ \text{acetone} \end{array} & \text{(I)} & \begin{array}{l} \text{Minimum} \\ \text{boiling} \\ \text{azeotrope} \end{array} \\ \hline \text{(B)} & \begin{array}{l} \text{Solution of ethanol} \\ \text{and water} \end{array} & \text{(II)} & \text{Dimerizes} \\ \hline \text{(C)} & \begin{array}{l} \text{Solution of benzene} \\ \text{and toluene} \end{array} & \text{(III)} & \begin{array}{l} \text{Maximum} \\ \text{boiling} \\ \text{azeotrope} \end{array} \\ \hline \text{(D)} & \begin{array}{l} \text{Solution of acetic} \\ \text{acid in benzene} \end{array} & \text{(IV)} & \Delta \mathrm{V}_{\text {mix }}=0 \\ \hline \end{array}$ Choose the correct answer from the options given below :
When 1 g each of compounds AB and $\mathrm{AB}_2$ are dissolved in 15 g of water separately, they increased the boiling point of water by 2.7 K and 1.5 K respectively. The atomic mass of A (in amu) is ____ $\times 10^{-1}$ (Nearest integer) (Given : Molal boiling point elevation constant is $\left.0.5 \mathrm{~K} \mathrm{~kg} \mathrm{~mol}^{-1}\right)$
Consider the given plots of vapour pressure (VP) vs temperature(T/K). Which amongst the following options is correct graphical representation showing $\Delta \mathrm{T}_{\mathrm{f}}$, depression in the freezing point of a solvent in a solution?