NEET UG 2023 — Physical Chemistry

Incorrect set of quantum numbers from the following is

For a reaction $3 \mathrm{~A} \rightarrow 2 \mathrm{~B}$ The average rate of appearance of $B$ is given by $\frac{\Delta[B]}{\Delta t}$. The correct relation between the average rate of appearance of $B$ with the average rate of disappearance of $A$ is given in option

Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R: Assertion A: Helium is used to dilute oxygen in diving apparatus. Reasons R: Helium has high solubility in ${O}_{2}$ In the light of the above statements, choose the correct answer from the options given below:

Consider the following reaction: $2 \mathrm{H}_2(\mathrm{~g})+\mathrm{O}_2(\mathrm{~g}) \rightarrow 2 \mathrm{H}_2 \mathrm{O}(\mathrm{g}) \Delta_{\mathrm{r}} \mathrm{H}^{\circ}=-483.64 \mathrm{~kJ}$. What is the enthalpy change for decomposition of one mole of water? (Choose the right option).

The right option for the mass of ${\mathrm{CO}}_{2}$ produced by heating $20g$ of $20%$ pure limestone is (Atomic mass of $\mathrm{Ca}=40$) $[{\mathrm{CaCO}}_{3}\overset{1200K}{\rightarrow }\mathrm{CaO}+{\mathrm{CO}}_{2}]$

The pH of a neutral solution at 25°C is

The element expected to form largest ion to achieve the nearest noble gas configuration is :

An acidic buffer is prepared by mixing:

Given below are two statements: one labelled as Assertion A and other is labelled as Reason R: Assertion A: A reaction can have zero activation energy Reason R: The minimum extra amount of energy absorbed by reactant molecules so that their energy becomes equal to threshold value, is called activation energy.

Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R: Assertion A: In equation ${\Delta }_{r}G=-{\mathrm{nFE}}_{\mathrm{cell}}$ value of ${\Delta }_{r}G$ depends on $n$. Reasons R: ${E}_{\mathrm{cell}}$ is an intensive property and ${\Delta }_{r}G$ is an extensive property. In the light of the above statements, choose the correct answer from the options given below:

The relation between ${n}_{m}$ (${n}_{m}=$the number of permissible values of magnetic quantum number $(m)$) for a given value of azimuthal quantum number $(l)$, is

The correct value of cell potential in volt for the reaction that occurs when the following two half cells are connected, is $\begin{aligned} & \mathrm{Fe}_{(\mathrm{aq})}^{2+}+2 \mathrm{e}^{-} \rightarrow \mathrm{Fe}(\mathrm{s}), \mathrm{E}^{\circ}=-0.44 \mathrm{~V} \\ & \mathrm{Cr}_2 \mathrm{O}_7^{2-}(\mathrm{aq})+14 \mathrm{H}^{+}+6 \mathrm{e}^{-} \rightarrow 2 \mathrm{Cr}^{3+}+7 \mathrm{H}_2 \mathrm{O}, \mathrm{E}^0=+1.33 \mathrm{~V} \\ & \end{aligned}$

On balancing the given redox reaction $a{\mathrm{Cr}}_{2}{O}_{7}^{2-}+{\mathrm{bSO}}_{3}^{2-}(\mathrm{aq})+{\mathrm{cH}}^{+}(\mathrm{aq})\overset{}{\rightarrow }2{\mathrm{aCr}}^{3+}(\mathrm{aq})+{\mathrm{bSO}}_{4}^{2-}(\mathrm{aq})+\frac{c}{2}{H}_{2}O(l)$ The coefficients $a,b,c$are found to be respectively

The conductivity of centimolar solution of $\mathrm{KCl}$ at $25^{\circ}C$ is $0.0210{\mathrm{ohm}}^{-1}{\mathrm{cm}}^{-1}$ and the resistance of the cell containing the solution at $25^{\circ}C$ is $60\mathrm{ohm}$. The value of cell constant is

Which amongst the following aqueous solutions of electrolytes will have minimum elevation in boiling point? Choose the correct option.

Which one of the following represents all isoelectronic species?

For a weak acid $\mathrm{HA}$, the percentage of dissociation is nearly $1 \%$ at equilibrium. If the concentration of acid is $0.1 \mathrm{~mol} \mathrm{~L}^{-1}$, then the correct option for its $\mathrm{K}_{\mathrm{a}}$ at the same temperature is

Select the correct statements from the following : A. Atoms of all elements are composed of two fundamental particles. B. The mass of the electron is $9.10939\times {10}^{-31}\mathrm{kg}$. C. All the isotopes of a given element show same chemical properties. D. Protons and electrons are collectively known as nucleons. E. Dalton's atomic theory, regarded the atom as an ultimate particle of matter. Choose the correct answer from the options given below:

The $E^{\ominus}$ values for $\begin{aligned} & \mathrm{Al}^{+} / \mathrm{Al}=+0.55 \mathrm{~V} \text { and } \mathrm{Tl}^{+} / \mathrm{TI}=-0.34 \mathrm{~V} \\ & \mathrm{Al}^{3+} / \mathrm{Al}=-1.66 \mathrm{~V} \text { and } \mathrm{Tl}^{3+} / \mathrm{TI}=+1.26 \mathrm{~V}\end{aligned}$ Identify the incorrect statement.

Which amongst the following options is the correct relation between change in enthalpy and change in internal energy?

The correct option for the rate law that corresponds to overall first order reaction is

Amongst the given options which of the following molecules/ion acts as a Lewis acid?

Molar conductance of an electrolyte increases with dilution according to the equation: $\Lambda_{\mathrm{m}}=\Lambda_{\mathrm{m}}^{\circ}-\mathrm{A} \sqrt{\mathrm{c}}$ Which of the following statements are true? (A) This equation applies to both strong and weak electrolytes. (B) Value of the constant A depends upon the nature of the solvent. (C) Value of constant $\mathrm{A}$ is same for both $\mathrm{BaCl}_2$ and $\mathrm{MgSO}_4$. (D) Value of constant $A$ is same for both $\mathrm{BaCl}_2$ and $\mathrm{Mg}(\mathrm{OH})_2$. Choose the most appropriate answer from the options given below.

The correct option for a redox couple is

For a certain reaction, the rate $=k[A{]}^{2}[B]$, when the initial concentration of A is tripled keeping concentration of B constant, the initial rate would

The density of $1 \mathrm{M}$ solution of a compound ' $X$ ' is $1.25 \mathrm{~g} \mathrm{~mL}^{-1}$. The correct option for the molality of solution is (Molar mass of compound $X=85 \mathrm{~g}$ )

Given below are two statements : Statement I : The value of wave function, $\psi$ depends upon the coordinates of the electron in the atom. Statement II : The probability of finding an electron at a point within an atom is proportional to the orbital wave function. In the light of the above statements, choose the correct answer from the options given below.

The equilibrium concentrations of the species in the reaction $A+B\rightleftharpoons C+D$ are $2,3,10\mathrm{and}6\mathrm{mol}{L}^{-1}$ respectively at $300K$. $\Delta {G}^{\circ }$ for the reaction is $(R=2\mathrm{cal}/\mathrm{mol}K)$