Physical Chemistry PYQ — Page 12

Magnetic moment $2.83$ BM is given by which of the following ions? (At.nos. $Ti=22,Cr=24, Mn=25, Ni=28)$

Calculate the energy in corresponding to light of wavelength $45 nm:$ (Planck’s constant $h=6.63\times {10}^{-34}Js:speed of light c=3\times {10}^{8} m{s}^{-1})$

What is the maximum number of orbitals that can be identified with the following quantum number $n=3, l=1, m=0$?

For the reversible reaction: ${N}_{2}(g)+3{H}_{2}(g)\rightleftharpoons 2N{H}_{3}(g)+heat$ The equilibrium shifts in forward direction:

Using the Gibbs change, $\Delta {G}^{o}=+63.3 kJ,$ for the following reaction, $A{g}_{2}C{O}_{3}(g) \rightleftharpoons 2A{g}^{+}(aq)+C{O}_{3}^{2-}(aq)$ the ${K}_{sp}$ of $A{g}_{2}C{O}_{3}(s)$ in water at ${25}^{o}C$ is $(R=8.314 J{K}^{-1}mo{l}^{-1})$

$B{e}^{2+}$ is isoelectronic with which of the following ions?

$1.0 g$ of magnesium is burnt with $0.56 g$ ${O}_{2}$ in a closed vessel. Which reaction is left in excess and how much? (At, wt. $Mg=24;O=16)$

The weight of silver (at.wt. $=108$) displaced by a quantity of electricity which displaces $5600 mL$ of ${O}_{2}$ at $\mathrm{STP}$ will be

For a reaction between $A$ and $B$ the order with respect to $A$ is 2 and the other with respect to $B$ is 3 . The concentrations of both $\mathrm{A}$ and $\mathrm{B}$ are doubled, the rate will increase by a factor of:

Maximum deviation from ideal gas is expected from

Accumulation of lactic acid $\left(\mathrm{HC}_3 \mathrm{H}_5 \mathrm{O}_3\right)$, a monobasic acid in tissues leads to pain and a feeling of fatigue. In a 0.10 $\mathrm{M}$ aqueous solution, lactic acid is $3.7 \%$ dissociates. The value of dissociation constant, $\mathrm{K}_a$, for this acid will be:

What is the maximum numbers of electrons that can be associated with the following set of quantum numbers? $n=3, l=1$ and $m=-1$

According to law of photochemical equivalence the energy absorbed (in erg/ mole $)$ is given as $\left(h=6.62 \times 10^{-27}\right.$ ergs, $\mathrm{c}=3 \times 10^{10} \mathrm{~cm} \mathrm{~s}^{-1}, \mathrm{~N}_{\mathrm{A}}=6.02 \times 10^{-23}$ $\left.\mathrm{mol}^{-1}\right)$ :

A magnetic moment of $1.73 \mathrm{BM}$ will be shown by one among the following

An excess of $\mathrm{AgNO}_3$ is added to $100 \mathrm{~mL}$ of a $0.01 \mathrm{M}$ solution of dichlorotetraaquachromium (III) chloride. The number of moles of AgCl precipitate would be

Three thermochemical equation are given below: (i) $\underset{\mathrm{kJJ} \mathrm{mol}^{-1}}{\mathrm{C}_{\text {(graphite) }}}+\mathrm{O}_{2(\mathrm{~g})} \rightarrow \mathrm{CO}_{2(g)} \Delta \mathrm{H}^{\circ}=x$ (iii) $\mathrm{CO}_{(\mathrm{gJ})}+1 / 2 \mathrm{O}_{2(\mathrm{gk}} \rightarrow \mathrm{CO}_{2(\mathrm{~g}) i} \Delta \mathrm{H}^{\circ}=\mathrm{z}$ Based on the above equations, find out which of the relationship given below is correct.

A reaction having equal energies of activation for forward and reverse reactions has

At $100^{\circ} \mathrm{C}$ the $\mathrm{K}_w$ of water is 55 times its value at $25^{\circ} \mathrm{C}$. What will be the $\mathrm{pH}$ of neutral solution? $(\log 55=1.74)$

When 5 litres of a gas mixture of methane and propane is perfectly combusted at $0^{\circ} \mathrm{C}$ and 1 atmosphere, 16 litres of oxygen at the same temperature and pressure is consumed. The amount of heat released from the combustion in kJ $\left(\triangle \mathrm{H}_{\text {eomb }}\left(\mathrm{CH}_4\right)\right.$ $=890 \mathrm{~kJ} \mathrm{~mol}^{-1}, \Delta \mathrm{H}_{\text {comb }}\left(\mathrm{C}_3 \mathrm{H}_8\right)=2220 \mathrm{~kJ}$ $\left.\mathrm{mol}^{-1}\right)$

How many grams of concentrated nitric acid solution should be used to prepare $250 \mathrm{~mL}$ of $2.0 \mathrm{M} \mathrm{HNO}_3$ ? The concentrated acid is $70 \% \mathrm{HNO}_3$.

Consider the half-cell reduction reaction: $$ \begin{aligned} & \mathrm{Mn}^{2+}+2 e^{-} \rightarrow \mathrm{Mn}, \mathrm{E}^{\mathrm{o}}=-1.18 \mathrm{~V} \\ & \mathrm{Mn}^{2+} \rightarrow \mathrm{Mn}^{3+}+e^{-}, \mathrm{E}^{\mathrm{o}}=1.51 \mathrm{~V} \end{aligned} $$ The $\mathrm{E}^{\circ}$ for the reaction $3 \mathrm{Mn}^{2+} \rightarrow \mathrm{Mn}^0$ $+2 \mathrm{Mn}^{3+}$, and possibility of the forward reaction are respectively

Based on equation $E=-2.178 \times 10^{-18} \mathrm{~J}\left(\frac{Z^2}{n^2}\right)$ certain conclusions are written. Which of them is not correct?

What is the activation energy for a reaction if its rate doubles when the temperature is raised from $20^{\circ} \mathrm{C}$ to $35^{\circ} \mathrm{C} ?\left(R=8.314 \mathrm{~J} \mathrm{~mol}^{-1} \mathrm{~K}^{-1}\right)$

$6.02 \times 10^{20}$ molecules of urea are present in $100 \mathrm{~mL}$ of its solution. The concentration of solution is