List of top Physical Chemistry Questions asked in IIT JAM CY

The d spacing for the first-order X-ray ($\lambda$= 1.54 Å) diffraction event of metallic iron (fcc) at $2\theta= 20.2°$ is _______.Å. (round off to three decimal places)

The volume fraction for an element in an fcc lattice is ____________ . (round off to two decimal places)

steady current of 1.25 A is passed through an electrochemical cell for 1.5 h using a 12 V battery. The total charge, Q, drawn during this process is __________ Coulombs. (round off to the nearest integer)

Iron is extracted from its ore via the reaction
$Fe_2O_3, + 3 CO→ 2 Fe + 3CO_2$
The volume of CO (at STP) required to produce 1 kg of iron is ________liters. (round off to the nearest integer)
[Given: Atomic wt. of Fe = 56; assume STP to be 0 °C and 1 atm]

A galvanic electrochemical cell made of Zn²⁺/Zn and Cu²⁺/Cu half-cells produces 1.10 V at 25°C. The ratio of |Zn²⁺| to |Cu²⁺| is maintained at 1.0. The ΔG° for the reaction when 1.0 mol of Zn gets dissolved is____kJ. (round off to the nearest integer)
[Given: Faraday's constant = 96485 C mol^-1]

At constant volume, 1.0 kJ of heat is transferred to 2 moles of an ideal gas at 1 atm and 298 K. The final temperature of the ideal gas is ____K. (round off to one decimal place)
[Given: R = 8.314 J K^-1 mol^-1]

Two close lying bands in a UV spectrum occur at 274 nm and 269 nm. The magnitude of the energy gap between the two bands is ____cm^-1. (round off to the nearest integer)

The pH of an aqueous buffer prepared using CH3COOH and CH3COO Na⁺ is 4.80.
The quantity $\frac{[CH_3COO^-]-[CH_3COOH]}{[CH_3COOH]}$ is _____. (round off to three decimal places)
[Given: pK_a of CH₃COOH in water is 4.75]

At constant temperature, 6.40 g of a substance dissolved in 78 g of benzene decreases the vapor pressure of benzene from 0.125 atm to 0.119 atm. The molar mass of the substance is ____g mol^-1. (round off to one decimal place)
[Given: Mol. wt. of benzene = 78 g mol^-1]

The longest wavelength of light absorbed by a hydrogen-like atom is 2.48 nm. The nuclear charge (Z) of the atom is ........
(Round off to nearest integer) (Rydberg constant $ R_{\infty} = 109700 \, \text{cm}^{-1} $)

Fullerene (C₆₀) crystallizes in an FCC unit cell (edge length = 14.14 Å) with one C₆₀ centered at each lattice point. The smallest distance (in Å) between the centers of two C₆₀ molecules is ..........
(Round off to two decimal places)

A film of stearic acid partially covers the water surface in a container. The work needed to decrease this coverage by 1 cm² is 25.0 × 10⁻⁷ J. The surface tension (in N/m) of the film is .......
(Round off to three decimal places)
(Surface tension of pure water is 0.072 N/m)

The heat of formation of MgO at 300 K and 1 bar pressure is -600.60 kJ mol$^{-1}$. The free energy (in kJ mol$^{-1}$) of formation of MgO at 280 K is ......... (Round off to nearest integer)

Sea water containing 1 M NaCl has to be desalinated at 300 K using a membrane permeable only to water. The minimum pressure (in bars) required on the sea-water side of the membrane is ......... (Round off to one decimal place)

A bacterial colony grows via cell division where each mother bacterium independently produces two daughter cells in 20 minutes. If the concentration of bacteria is $ 10^4 \, \text{cm}^{-3} $, the colony becomes harmful. Starting from a colony with an initial concentration of 5 cm$^{-3}$, the time taken (in minutes) for the colony to become harmful is ......... (Round off to nearest integer)

The Maxwell distribution of speeds of a gas at 300 K is given below. The molar mass (in g mol$^{-1}$) of this gas is ......... (Round off to one decimal place) (R = 8.3 J mol$^{-1}$ K$^{-1}$)

At a certain wavelength, liquid P transmits 70%, whereas liquid Q transmits 30% of the incident light when separately placed in a spectrophotometric cell (path length = 1 cm). In a binary mixture of liquids P and Q (assume non-interacting liquids), the absorbance in the same cell is 0.25. The volume fraction of liquid P in the binary mixture is .......... (Round off to two decimal places)

The mean ionic activity coefficient for a 0.01 M aqueous solution of Ca$_3$(PO$_4$)$_2$ is .......... (Round off to three decimal places) (Given: $ \log_{10} \gamma_{\pm} = -0.509 Z_{\pm}^2 \sqrt{T} $)

For the reaction, CuSO$_4$ (aq) + Zn (s) → ZnSO$_4$ (aq) + Cu (s), the value of $ \Delta G^\circ $ (in kJ mol$^{-1}$) is .......... (Round off to the nearest integer) (Reduction potential: Cu$^{2+}$(aq)/Cu(s) = +0.34 V; Zn$^{2+}$(aq)/Zn(s) = -0.76 V))

The compound(s) which will have only two signals in the $ ^1 \text{H} $ NMR spectrum in 3:2 ratio is(are)

The boron adduct(s), which show(s) three signals in $ ^1 \text{H} $ NMR spectrum with the intensity ratio 1:2:3 is(are)

In water, the enthalpy of a protein in its folded state ($H_f$) is lower than that in its unfolded state ($H_{UF}$). The entropies of the folded and unfolded states are $S_f$ and $S_{UF}$, respectively. The condition(s) under which this protein spontaneously folds in water at a temperature $T$, is(are)

$\psi(x,y,z)$ describes the wavefunction of a particle. The probability of finding the particle between $x$ and $x+dx$, $y$ and $y+dy$, and $z$ and $z+dz$, can be expressed as

For the reaction shown in Scheme 1, the concentration profiles of different species are provided.
$\text{Scheme 1:}$

Based on this graph, the correct condition(s) regarding the rate constants is(are)

The solid state structure of HF is