JEE Main 2003 — Physical Chemistry

If liquids $\mathrm{A}$ and $\mathrm{B}$ form an ideal solution

Consider the reaction equilibrium $2 \mathrm{SO}_2(\mathrm{~g})+\mathrm{O}_2(\mathrm{~g}) \rightleftharpoons 2 \mathrm{SO}_3(\mathrm{~g}) ; \Delta \mathrm{H}^0=-198 \mathrm{~kJ}$. On the basis of Le Chatelier's principle, the condition favourable for the forward reaction is

The solubility in water of a sparingly soluble salt $\mathrm{AB}$ is $1.0 \times 10^{-5} \mathrm{~mol} \mathrm{~L}^{-1}$. Its solubility product number will be

If at $298 \mathrm{~K}$ the bond energies of $\mathrm{C}-\mathrm{H}, \mathrm{C}-\mathrm{C}, \mathrm{C}=\mathrm{C}$ and $\mathrm{H}-\mathrm{H}$ bonds are respectively $414,347,615$ and $435 \mathrm{~kJ}$ $\mathrm{mol}^{-1}$, the value of enthalpy change for the reaction $\mathrm{H}_2 \mathrm{C}=\mathrm{CH}_2(\mathrm{~g})+\mathrm{H}_2(\mathrm{~g}) \rightarrow \mathrm{H}_3 \mathrm{C}-\mathrm{CH}_3(\mathrm{~g})$ at $298 \mathrm{~K}$ will be

The de Broglie wavelength of a tennis ball of mass $60 \mathrm{~g}$ moving with a velocity of 10 metres per second is approximately

The half-life of a radioactive isotope is three hours. If the initial mass of the isotope were $256 \mathrm{~g}$, the mass of it remaining undecayed after 18 hours would be

The enthalpy change for a reaction does not depend upon

In an irreversible process taking place at constant $\mathrm{T}$ and $\mathrm{P}$ and in which only pressure-volume work is being done, the change in Gibbs free energy (dG) and change in entropy (dS), satisfy the criteria

In Bohr series of lines of hydrogen spectrum, the third line from the red end corresponds to which one of the following inter-orbit jumps of the electron for Bohr orbits in an atom of hydrogen

Standard reduction electrode potentials of three metals A,B\&C are respectively $+0.5 \mathrm{~V},-3.0 \mathrm{~V} \&-1.2 \mathrm{~V}$. The reducing, powers of these metals are

What volume of hydrogen gas, at $273 \mathrm{~K}$ and $1 \mathrm{~atm}$, pressure will be consumed in obtaining $21.6 \mathrm{~g}$ of elemental boron (atomic mass $=10.8$ ) from the reducti on of boron trichloride by hydrogen?

Which one of the following statements is not true?

A pressure cooker reduces cooking time for food because

Which one of the following groupings represents a collection of isoelectronic species? (At. nos,: 55, Br:35)

$25 \mathrm{ml}$ of a solution of barrium hydroxide on titration with a $0.1$ molar solution of hydrochloric acid gave a litre value of $35 \mathrm{ml}$. The molarity of barium hydroxide solution was

When rain is accompanied by a thunderstorm, the collected rain water will have a $\mathrm{pH}$ value

The orbital angular momentum for an electron revolving in an orbit is given by $\sqrt{l(l+1)} \cdot \frac{\mathrm{h}}{2 \pi}$. This momentum for an s-electron will be given by

Which of the following could act as apropellant for rockets?

For a cell reaction involving a two-electron change, the standard e.m.f. of the cell is found to be $0.295 \mathrm{~V}$ at $25^{\circ} \mathrm{C}$. The equilibrium constant of the reaction at $25^{\circ} \mathrm{C}$ will be

In a $0.2$ molal aqueous solution of a weak acid $\mathrm{HX}$ the degree of ionization is $0.3$. Taking $\mathrm{k}_{\mathrm{f}}$ for water as $1.85$, the freezing point of the solution will be nearest to

For the redox reaction $\mathrm{Zn}(\mathrm{s})+\mathrm{Cu}^{2+}(0.1 \mathrm{M}) \rightarrow \mathrm{Zn}^{2+}(1 \mathrm{M})+\mathrm{Cu}(\mathrm{s})$ taking place in a cell, $\mathrm{E}_{\text {cell }}^0$ is $1.10$ volt. $\mathrm{E}^{\circ}$ for the cell will be $\left(2.303 \frac{\mathrm{RT}}{\mathrm{F}}=0.0591\right)$

The rate law for a reaction between the substances $\mathrm{A}$ and $\mathrm{B}$ is given by Rate $=\mathrm{k}[\mathrm{A}]^{\mathrm{n}}[\mathrm{B}]^{\mathrm{m}}$ On doubling the concentration of A and halving the concentration of B, the ratio of the new rate to the earlier rate of the reaction will be as

The internal energy change when a system goes from state $\mathrm{A}$ to $\mathrm{B}$ is $40 \mathrm{~kJ} / \mathrm{mole}$. If the system goes from $\mathrm{A}$ to $\mathrm{B}$ by a reversible path and retums to state $\mathrm{A}$ by an irreversible path what would be the net change in internalenergy?

In respect of the equation $\mathrm{k}=\mathrm{Ae}^{-\mathrm{E}_{\mathrm{o}} / \mathrm{RT}}$ in chemical kinetics, which one of the following statements is correct?

For the reaction system: $2 \mathrm{NO}(\mathrm{g})+\mathrm{O}_2(\mathrm{~g}) \rightarrow 2 \mathrm{NO}_2(\mathrm{~g})$ volume is suddenly reduce to half its value by increasing the pressure on it. If the reaction is of first order with respect to $\mathrm{O}_2$ and second order with respect to $\mathrm{NO}$, the rate of reaction will

When during electrolysis of a solution of $\mathrm{AgNO}_3 9650$ coulombs of charge pass through the electroplating bath, the mass of silver deposited on the cathode will be

The correct relationship between free energy change in a reaction and the corresponding equilibrium constant $\mathrm{K}_{\mathrm{c}}$ is

For the reaction equilibrium $\mathrm{N}_2 \mathrm{O}_4(\mathrm{~g}) \rightleftharpoons 2 \mathrm{NO}_2(\mathrm{~g})$ the concentrations of $\mathrm{N}_2 \mathrm{O}_4$ and $\mathrm{NO}_2$ at equilibrium are $4.8 \times 10^{-2}$ and $1.2 \times 10^{-2} \mathrm{~mol} \mathrm{~L}^{-1}$ respectively. The value of $\mathrm{K}_{\mathrm{c}}$ for the reaction is