JEE Main Chemistry — Physical Chemistry previous year questions with solutions.
The solubility of $\mathrm{AgCN}$ in a buffer solution of $\mathrm{pH}=3$ is $x$. The value of $x$ is: [Assume : No cyano complex is formed ; ${K}_{\mathrm{sp}}(\mathrm{AgCN})=2.2\times {10}^{-16}$ and ${K}_{a}(\mathrm{HCN})=6.2\times {10}^{-10}$]
The species given below that does $\mathrm{NOT}$ show disproportionation reaction is:
$4g$ equimolar mixture of $\mathrm{NaOH}$ and ${\mathrm{Na}}_{2}{\mathrm{CO}}_{3}$ contains $\mathrm{xg}$ of $\mathrm{NaOH}$ and $\mathrm{yg}$ of ${\mathrm{Na}}_{2}{\mathrm{CO}}_{3}.$ The value of $x$ is $g.$ (Nearest integer)
In basic medium ${\mathrm{CrO}}_{4}^{2-}$ oxidises ${S}_{2}{O}_{3}^{2-}$ to form ${{\mathrm{SO}}_{4}}^{2-}$ and itself changes into $\mathrm{Cr}{(\mathrm{OH})}_{4}^{-}$.The volume of $0.154{\mathrm{MCrO}}_{4}^{2-}$ required to react with $40\mathrm{mL}$ of $0.25{\mathrm{MS}}_{2}{{O}_{3}}^{2-}$ is _____ $\mathrm{mL}.$ (Rounded-off to the nearest integer)
The reaction that occurs in a breath analyser, a device used to determine the alcohol level in a person's blood stream is $2{K}_{2}{\mathrm{Cr}}_{2}{O}_{7}+8{H}_{2}{\mathrm{SO}}_{4}+3{C}_{2}{H}_{6}O\rightarrow 2{\mathrm{Cr}}_{2}{({\mathrm{SO}}_{4})}_{3}+3{C}_{2}{H}_{4}{O}_{2}+2{K}_{2}{\mathrm{SO}}_{4}+11{H}_{2}O$ If the rate of appearance of ${\mathrm{Cr}}_{2}{({\mathrm{SO}}_{4})}_{3}$ is $2.67\mathrm{mol}{\mathrm{min}}^{-1}$ at a particular time, the rate of disappearance of ${C}_{2}{H}_{6}O$ at the same time is mol ${\mathrm{min}}^{-1}.$ (Nearest integer)
The vapour pressures of $A$ and $B$ at $25^{\circ}C$ are $90\mathrm{mmHg}$ and $15\mathrm{mm}\mathrm{Hg}$ respectively. If $A$ and $B$ are mixed such that the mole fraction of $A$ in the mixture is $0.6,$ then the mole fraction of $B$ in the vapour phase is $x\times {10}^{-1}.$ The value of $x$ is (Nearest integer)
It is true that:
The figure that is not a direct manifestation of the quantum nature of atom is :
The volume $(inmL)$ of $0.125M{AgNO}_{3}$ required to quantitatively precipitate chloride ions in $0.3g$ of $[Co{(N{H}_{3})}_{6}]C{l}_{3}$ is __________. $[Co{(N{H}_{3})}_{6}]MC{l}_{3}=267.46g/mol$ ${AgNOM}_{3}=169.87g/mol$ Report the nearest integer as the answer.
For one mole of an ideal gas, which of these statements must be true? (a) Internal energy $(U)$ and enthalpy $(H)$ each depends on temperature. (b) Compressibility factor $Z$ is not equal to 1 (c) ${C}_{P,m}–{C}_{V,m}=R$ (d) $\mathrm{dU}={C}_{v}\mathrm{dT}$ for any process
Preparation of Bakelite proceeds via reactions:
Oxidation number of potassium in ${K}_{2}O,{K}_{2}{O}_{2}$ and $K{O}_{2},$ respectively, is:
The unit of rate constant for a zero order reaction is:
According to Raoults law, the relative lowering of vapor pressure of a solution is equal to:
A graph of vapour pressure and temperature for three different liquids $X,Y$ and $Z$ is shown below:  The following inferences are made: $(A)X$ has higher intermolecular interactions compared to $Y.$ $(B)X$ has lower intermolecular interactions compared to $Y.$ $(C)Z$ has lower intermolecular interactions compared to $Y.$ The correct inferences is/are:
The equation that is incorrect is:
Amongst the following statements, that which was not proposed by Dalton was :
Amongst the following, the form of water with the lowest ionic conductance at $298K$ is:
The difference between the radii of ${3}^{\mathrm{rd}}$ and ${4}^{\text{th }}$ orbits of ${L}_{i}^{2+}$ is ${\Delta R}_{1}$. The difference between the radii of ${3}^{\mathrm{rd}}$ and ${4}^{\text{th }}$ orbits of ${\mathrm{He}}^{+}$ $\Delta {R}_{2}.$ Ratio $\Delta {R}_{1}:\Delta {R}_{2}$ is :
Let ${C}_{\mathrm{NaCl}}$ and ${{C}_{\mathrm{BaSO}}}_{4}$, be the conductances (in S) measured for saturated aqueous solutions of $\mathrm{NaCl}$ and $BaS{O}_{4}$ respectively, at a temperature T. Which of the following is false?
$108 g$ of silver (molar mass $108 g{mol}^{-1}$ ) is deposited at cathode from ${AgNO}_{3}(aq)$ solution by a certain quantity of electricity. The volume (in $L$ ) of oxygen gas produced at $273 K$ and $1$ bar pressure from water by the same quantity of electricity is ________
Two open beakers one containing a solvent and the other containing a mixture of that solvent with a non volatile solute are together sealed in a container. Over time:
For the following Assertion and Reason, the correct option is: Assertion: The $pH$ of water increases with increase in temperature. Reason: The dissociation of water into ${H}^{+}$ and $O{H}^{-}$ is an exothermic reaction.
If the solubility product of ${\mathrm{AB}}_{2}$ is $3.20\times {10}^{-11}{M}^{3}$, then the solubility of ${\mathrm{AB}}_{2}$ in pure water is _______ $\times {10}^{-4}\mathrm{mol}{L}^{-1}$ [Assuming that neither kind of ion reacts with water]