JEE Main 2015 — Physical Chemistry

A sample of a hydrate of barium chloride weighing 61 g was heated until all the water of hydration is removed. The dried sample weighed 52 g. The formula of the hydrated salt is: (atomic mass, Ba = 137 amu, Cl = 35.5 amu)

A solution at ${\text{20}}^{\text{o}}\text{C}$ is composed of 1.5 mol of benzene and 3.5 mol of toluene. If the vapour pressure of pure benzene and pure toluene at this temperature are 74.7 torr and 22.3 torr respectively, then the total vapour pressure of the solution and the benzene mole fraction in equilibrium with it will be, respectively:

A variable, the opposite external potential $({E}_{\mathrm{ext}})$ is applied to the cell $Zn | Z{n}^{2+} (1M)\parallel C{u}^{2+} (1 M)| Cu$, of potential $1.1V$. When ${E}_{ext}<1.1 V$ and ${E}_{ext}>1.1 V$, respectively electrons flow from

An element $X$ shows $+3$, oxidation state in its compounds. Out of the four compounds given below, choose the incorrect formula for the element $X$.

At temperature $T$, the average kinetic energy of any particle is $\frac{3}{2}\mathrm{kT}$. The de Broglie wavelength follows the order:

At $298K$, the standard reduction potentials are $1.51V$ for ${MnO}_{4}^{-} | M{n}^{2+}$, $1.36V$ for $C{l}_{2}|C{l}^{-}$, $1.07V$ for $B{r}_{2}|B{r}^{-}$, $0.54V$ for ${I}_{2}|{I}^{-}$. At $\mathrm{pH}=3$, permanganate is expected to oxidize: $(\frac{RT}{F}=0.059)$

Determination of the molar mass of acetic acid in benzene using freezing point depression is affected by:

For the equilibrium, $A(g)\rightleftharpoons B(g), \Delta H\mathrm{is}-40\mathrm{kJ}/\mathrm{mol}$ . If the ratio of the activation energies of the forward $({E}_{f})$ and reverse $({E}_{b})$ reactions is $\frac{2}{3}$ then:

Gaseous ${N}_{2}{O}_{4}$ dissociates into gaseous $N{O}_{2}$ according to the reaction ${N}_{2}{O}_{4}(g)\rightleftharpoons 2N{O}_{2}(g)$ At $300K$ and $1\mathrm{atm}$ pressure, the degree of dissociation of ${N}_{2}{O}_{4}$ is $0.2$. If one mole of ${N}_{2}{O}_{4}$ gas is contained in a vessel, then the density of the equilibrium mixture is$:$

Higher order (>3) reactions are rare due to:

If the principal quantum number $\text{n}=6,$ the correct sequence of filling of electrons will be:

In the following reaction: $A+2B+3C\rightleftharpoons A{B}_{2}{C}_{3}$ $6.0g$ of $A$, $6.0\times {10}^{23}$ atoms of $B$ and $0.036\mathrm{mol}$ of $C$ reacted and formed $4.8g$ of compound $A{B}_{2}{C}_{3}$. If the atomic mass of $A$ and $C$ are $60$ and $80\mathrm{amu}$, respectively. What is the atomic mass of $B$ in $\mathrm{amu}$? (Avogadro number$=6\times {10}^{23}$)

The following reaction is performed at $298K$. $2NO(g)+{O}_{2}(g)\rightleftharpoons 2N{O}_{2}(g)$ The standard free energy of the formation of $NO(g)$ is $86.6\mathrm{kJ}{\mathrm{mol}}^{-1}$ at $298K$. What is the standard free energy of the formation of $N{O}_{2}(g)$ at $298K$? $({K}_{P}=1.6\times {10}^{12})$

The heat of atomization of methane and ethane are $360\mathrm{kJ}{\mathrm{mol}}^{-1}$ and $620\mathrm{kJ}{\mathrm{mol}}^{-1}$, respectively. The longest wavelength of light capable of breaking the $C-C$ bond is (Avogadro's number$=6.023\times {10}^{23}, h=6.62\times {10}^{-34} J s$)

The increase of pressure on $ice \rightleftharpoons water$ system at constant temperature will lead to:

The molecular formula of a commercial resin used for exchanging ions in water softening is ${C}_{8}{H}_{7}S{O}_{3}Na$ $(\mathrm{molecular}\mathrm{weight}=206)$. What would be the maximum uptake of $C{a}^{2+}$ ions by the resin if expressed in $\mathrm{mol}$ per $\mathrm{gm}$?

$A+2B\rightarrow C$ , the rate equation for the reaction is given as Rate $=k[A][B]$ If the concentration of A is kept the same but that of B is doubled what will happen to the rate itself?

The reaction $2{N}_{2}{O}_{5}(g)\rightarrow 4N{O}_{2}(g)+{O}_{2}(g)$ follows first order kinetics. The pressure of a vessel containing only ${N}_{2}{O}_{5}$ was found to increase from 50 mm Hg to 87.5 mm Hg in 30 min. The pressure exerted by the gases after 60 min. Will be (Assume temperature remains constant) :

The standard Gibbs energy change at 300 K for the reaction $2A\rightleftharpoons B+C$ is 2494.2 J. At a given time, the composition of the reaction mixture is $[A]=\frac{1}{2}, [B]=2$ and $[C]=\frac{1}{2}$ . The reaction proceeds in the: $[R=8.314 J/K-mol , e=2.718]$ {Given antilog (-0.44)=0.36}

The vapour pressure of acetone at ${20}^{o}C$ is $185\mathrm{torr}$. When $1.2g$ of a non-volatile substance was dissolved in $100g$ of acetone at ${20}^{o}C$ , its vapour pressure was $183\mathrm{torr}$. The molar mass $(g mo{l}^{-1})$ of the substance is:

Two Faraday of electricity is passed through a solution of $CuS{O}_{4}$ . The mass of copper deposited at the cathode is: (Atomic mass of Cu = 63.5 amu)

Which of the following is the energy of a possible excited state of hydrogen?