List of top Physical Chemistry Questions asked in Indian Institute Of Technology Joint Admission Test for MSc

Identify the reaction for which, at equilibrium, a change in the volume of the closed reaction vessel at a constant temperature will not affect the extent of the reaction

The function exp(−2(𝑥-1)²) attains a maximum at 𝑥= _______. (rounded off to the nearest integer)

The enthalpy change for the reaction
C(𝑔) +\( \frac{1}{2}\) O₂(𝑔)→CO(𝑔) is _______ kJ per mole of CO(𝑔) produced. 
(rounded off to one decimal place) 
[Given: 
C(𝑔)+O₂(𝑔) → CO₂(𝑔), ΔH_rxn = −393.5 kJ per mole of CO₂(𝑔) produced 
CO₂(𝑔) → CO(𝑔) +\( \frac{1}{2}\) O₂(𝑔), ΔH_rxn = 283.0 kJ per mole of CO(𝑔) produced]

The magnitude of energy difference between the energy levels 𝑛=3 and 𝑛=2 of a quantum particle of mass 𝑚 in a box of length L is \(\frac{Xℎ ^2}{ 8𝑚L ^2} .\) 
Then X = _______. 
(rounded off to the nearest integer) 
[Given: ℎ is Planck’s constant and 𝑛 denotes the quantum number]

The correct assumption(s) required to derive Langmuir adsorption isotherm is/are

For the following compound

the number of signals expected in the 1H NMR spectrum is _________.

Equal number of gas molecules A (mass 𝑚 and radius 𝑟) and B (mass 2𝑚 and radius 2𝑟) are placed in two separate containers of equal volume. At a given temperature, the ratio of the collision frequency of B to that of A is
(Assume the gas molecules as hard spheres)

An elementary reaction 2A→P follows a second order rate law with rate constant 2.5×10⁻³ dm³ mol⁻¹ s⁻¹ . The time required for the concentration of A to change from 0.4 mol dm⁻3 to 0.2 mol dm⁻³ is ___s.
(round off to the nearest integer)

The vapor pressure of a dilute solution of a non-volatile solute and the vapor pressure of the pure solvent at the same temperature are P and P*, respectively. \(\frac{P^*-P}{P^*}\) is equal to 
(Assume that the vapor phase behaves as an ideal gas)

The volume of water (in mL) required to be added to a 100 mL solution (aq. 0.1 M) of a weak acid (HA) at 25 °C to double its degree of dissociation is
[Given: K_a of HA at 25 °C=1.8 x10⁻⁵ ]

Adsorption of a gas on a solid surface follows the Langmuir isotherm. If \(\frac{ k_a}{k_d}\)=1.0 bar^-1 , the fraction of adsorption sites occupied by the gas at equilibrium under 2.0 bar pressure of the gas at 25 °C is 
( k_a and k_d are the rate constants for adsorption and desorption processes, respectively, at 25 °C)

The following diagram is obtained in a pH-metric titration of a weak dibasic acid (H₂A) with a strong base. The point that best represents [HA⁻]=[A ⁻² ] is

The diagram that best describes the variation of viscosity (𝜂) of water with temperature at 1 atm is

The system with the lowest zero-point energy when it is confined to a one dimensional box of length 𝐿 is

The standard reduction potential (E⁰ ) of Fe³⁺→Fe is____V.
[Given: Fe³⁺→Fe2+ E ⁰ = 0.77 V and 
Fe²⁺→Fe E ⁰=−0.44 V] 
(round off to three decimal places)

For the given elementary reactions, the steady-state concentration of X is

The isoelectric point of glutamic acid is ______.

(round off to two decimal places)

For the elementary reaction  At time 𝑡 = 0, [𝐀] = 𝐴₀ and [𝐁]=[𝐂]=0. At a later time 𝑡, the value of \(\frac{[B]}{[C]}\) is ______. (round off to the nearest integer)

The separation (in nm) of {134} planes of an orthorhombic unit cell (with cell parameters 𝑎=0.5 nm, 𝑏=0.6 nm, and 𝑐=0.8 nm) is

The spin-only magnetic moment of B₂ molecule is_____ μ_𝐵 .
(round off to two decimal places)

The amount of ethane produced in the following reaction is kg.

(round off to two decimal places)

The correct relation(s) for an ideal gas in a closed system is/are

The following diagram shows the kinetic energy of the ejected photoelectrons against the energy of incident radiation for two metal surfaces M₁ and M₂. If the energy of the incident radiation on M₁ is equal to the work function of M₂, the de Broglie wavelength of the ejected photoelectron is nm

[Given: Mass of electron = 9.11x10⁻³¹ kg; Planck’s constant = 6.62x10⁻³⁴ J s; 1 eV=1.6x10⁻¹⁹ J.]
(round off to two decimal places)

Consider the following reaction:
2 C₆H₆+15 O₂→12 CO₂+6 H₂O \(Δ_r𝐻^0_{298}\) =−3120 kJ mol⁻¹.
A closed system initially contains 5 moles of benzene and 25 moles of oxygen under standard conditions at 298 K. The reaction was stopped when 17.5 moles of oxygen is left. The amount of heat evolved during the reaction is____kJ. 
(round off to the nearest integer)