Physical Chemistry PYQ — Page 20

If a gas expands at constant temperature, it indicates that

In DNA, the complimentary bases are

The rate constants $\mathrm{k}_1$ and $\mathrm{k}_2$ for two different reactions are $10^{16} \cdot \mathrm{e}^{-2000 / T}$ and $10^{15} \cdot \mathrm{e}^{-1000 / T}$ respectively. The temperature at which $\mathrm{k}_1=\mathrm{k}_2$ is

Kohlrausch's law states that at

Green chemistry means such reactions which

Which of the following are not state functions? (I) $q+w$ (II) $q$ (III) $\mathrm{w}$ (IV) H-TS

What volume of oxygen gas $\left(\mathrm{O}_2\right)$ measured at $0^{\circ} \mathrm{C}$ and $1 \mathrm{~atm}$, is needed to burn completely $1 \mathrm{~L}$ of propane gas $\left(\mathrm{C}_3 \mathrm{H}_8\right)$ measured under the same conditions?

Bond dissociation enthalpy of $\mathrm{H}_2, \mathrm{Cl}_2$ and $\mathrm{HCl}$ are 434,242 and $431 \mathrm{kJmol}^{-}$ ${ }^1$ respectively. Enthalpy of formation of $\mathrm{HCl}$ is

With which one of the following elements silicon should be doped so as to give p-type of semiconductor?

The bromination of acetone that occurs in acid solution is represented by this equation. $\mathrm{CH}_3 \mathrm{COCH}_3(a q)+\mathrm{Br}_2(a q) \longrightarrow \mathrm{CH}_3 \mathrm{COCH}_2 \mathrm{Br}(a q)+\mathrm{H}^{+}(a q)+\mathrm{Br}^{-}(a q)$ These kinetic data were obtained for given reaction concentrations. $\begin{array}{|l|} \hline \text {Initial concentrations, } M & \\ \begin{array}{c|l|l|l} {\left[\mathrm{CH}_3 \mathrm{COCH}_3\right]} & {\left[\mathrm{Br}_2\right]} & {\left[\mathrm{H}^{+}\right]} & \text{Initial rate, disappearance of } \mathrm{Br}_2, \mathrm{Ms}^{-1} \\ \hline 0.30 & 0.05 & 0.05 & 5.7 \times 10^{-5} \\ 0.30 & 0.10 & 0.05 & 5.7 \times 10^{-5} \\ 0.30 & 0.10 & 0.10 & 1.2 \times 10^{-4} \\ 0.40 & 0.05 & 0.20 & 3.1 \times 10^{-4} \end{array} \\ \hline \end{array}$ Based on these data, the rate equation is

A galvanometer of resistance $50 \Omega$ is connected to a battery of $3 \mathrm{~V}$ along with a resistance of $2950 \Omega$ in series. A full scale deflection of 30 divisions is obtained in the galvanometer. In order to reduce this deflection to 20 divisions, the resistance in series should be

The angular shape of ozone molecule $\left(\mathrm{O}_3\right)$ consists of

The efficiency of a fuel cell is given by:

Calculate the $\mathrm{pOH}$ of a solution $25^{\circ} \mathrm{C}$ that contains $1 \times 10^{-10} \mathrm{M}$ of hydronium ions i.e. $\mathrm{H}_3 \mathrm{O}^{+}$:

A weak acid, HA and a $\mathrm{K}_a$ of $1.00 \times 10^{-5}$. If $0.100 \mathrm{~mol}$ of this acid is dissolved in one litre of water, the percentage of acid dissociated at equilibrium is closer to:

If $60 \%$, of a first order reaction was completed in 60 minutes, $50 \%$ of the same reaction would be completed in approximately: $$ (\log 4=0.60, \log 5=0.69) $$

Consider the following sets of quantum numbers: \(\begin{array}{|c|c|c|c|c|} \hline & n & l & m & s \\ \hline \text {(i) } & 3 & 0 & 0 & +1 / 2 \\ \text {(ii) } & 2 & 2 & 1 & +1 / 2 \\ \text {(iii) } & 4 & 2 & -2 & -1 / 2 \\ \text {(iv) } & 1 & 0 & -3 & -1 / 2 \\ \text {(v) } & 3 & 2 & 3 & +1 / 2 \\ \hline \end{array}\) Which of the following sets of quantum number is not possible?

In a first order reaction $\mathrm{A} \rightarrow \mathrm{B}$ if $k$ is rate constant and initial concentration of the reactant $\mathrm{A}$ is $0.5 \mathrm{M}$, then the half-life is:

A steady current of $1.5 \mathrm{amp}$ flows through a copper voltameter for 10 minutes. If the electrochemical equivalent of copper is 30 $\times 10^{-5} \mathrm{~g}$ coulomb $^{-1}$, the mass of copper deposited on the electrode will be.

Concentrated of aqueous sulphuric acid is $98 \% \mathrm{H}_2 \mathrm{SO}_4$ by mass and has a density of $1.80 \mathrm{~g} \mathrm{~mL}^{-1}$ Volume of acid required to make one litre of $0.1 \mathrm{M} \mathrm{H}_2 \mathrm{SO}_4$ solution is:

The equilibrium constant of the reaction: $\mathrm{Cu}_{(s)}+2 \mathrm{Ag}_{(a q)}^{+} \rightarrow \mathrm{Cu}_{(a q)}^{2+}+2 \mathrm{Ag}_{(s)}$ $\mathrm{E}^{\mathrm{o}}=0.46 \mathrm{~V}$ at $298 \mathrm{~K}$ is:

The number of moles $\mathrm{KMnO}_4$ that will be needed to react with one mole of sulphite ion in acidic solution is:

Consider the following reactions: (i) $\mathrm{H}_{(a q)}^{+}+\mathrm{OH}_{(a q)}^{-} \rightarrow \mathrm{H}_2 \mathrm{O}_{(\mathrm{i})}, \Delta \mathrm{H}$ $=-\mathrm{X}_1 \mathrm{~kJ} \mathrm{~mol}^{-1}$ (ii) $\mathrm{H}_{2(a q)}+\frac{1}{2} \mathrm{O}_{2(a q)} \rightarrow \mathrm{H}_2 \mathrm{O}_{(\mathrm{I})} \Delta \mathrm{H}$ $=-\mathrm{X}_2 \mathrm{~kJ} \mathrm{~mol}^{-1}$ (iii) $\mathrm{CO}_{2(\mathrm{~g})}+\mathrm{H}_{2(g)} \rightarrow \mathrm{CO}_{(g)}+\mathrm{H}_2 \mathrm{O}, \Delta \mathrm{H}$ $=-\mathrm{X}_3 \mathrm{~kJ} \mathrm{~mol}^{-1}$ (iv) $\mathrm{C}_2 \mathrm{H}_{2(g)}+\frac{5}{2} \mathrm{O}_{2(g)} \rightarrow 2 \mathrm{CO}_{2(g)}+\mathrm{H}_2 \mathrm{O}_{(i) \text {, }}$ $\Delta \mathrm{H}=+\mathrm{X}_4 \mathrm{~kJ} \mathrm{~mol}^{-1}$ Enthalpy of formation of $\mathrm{H}_2 \mathrm{O}_{(l)}$ is:

Given that bond energies of $\mathrm{H}-\mathrm{H}$ and $\mathrm{Cl}-\mathrm{Cl}$ are $430 \mathrm{~kJ} \mathrm{~mol}^{-1}$ and $240 \mathrm{~kJ}$ $\mathrm{mol}^{-1}$ respectively and $\Delta \mathrm{H}_{\mathrm{f}}$ for $\mathrm{HCl}$ is $-\mathrm{kJ}$ $\mathrm{mol}^{-1}$, bond enthalpy of $\mathrm{HCl}$ is: