JEE Advanced 2017 · Paper 1

An ideal gas is expanded from (p₁, V₁, T₁) to (p₂, V₂, T₂) under different conditions. The correct statement(s) among the following is(are)

1. AThe work done on the gas is maximum when it is compressed irreversibly from (p₂, V₂) to (p₁, V₁) against constant pressure p₁
2. BIf the expansion is carried out freely, it is simultaneously both isothermal as well as adiabatic
3. CThe work done by the gas is less when it is expanded reversibly from V₁ to V₂ under adiabatic conditions as compared to that when expanded reversibly from V₁ to V₂ under isothermal conditions
4. DThe change in internal energy of the gas is (i) zero, if it is expanded reversibly with T₁ = T₂, and (ii) positive, if it is expanded reversibly under adiabatic conditions with T₁ ≠ T₂

The correct statement(s) about the oxoacids, HClO₄ and HClO, is(are)

1. AThe central atom in both HClO₄ and HClO is sp³ hybridized
2. BHClO₄ is more acidic than HClO because of the resonance stabilization of its anion
3. CHClO₄ is formed in the reaction between Cl₂ and H₂O
4. DThe conjugate base of HClO₄ is weaker base than H₂O

The colour of the X₂ molecules of group 17 elements changes gradually from yellow to violet down the group. This is due to

1. Athe physical state of X₂ at room temperature changes from gas to solid down the group
2. Bdecrease in ionization energy down the group
3. Cdecrease in π*−σ* gap down the group
4. Ddecrease in HOMO-LUMO gap down the group

Addition of excess aqueous ammonia to a pink coloured aqueous solution of MCl₂·6H₂O (X) and NH₄Cl gives an octahedral complex Y in the presence of air. In aqueous solution, complex Y behaves as 1:3 electrolyte. The reaction of X with excess HCl at room temperature results in the formation of a blue coloured complex Z. The calculated spin only magnetic moment of X and Z is 3.87 B.M., whereas it is zero for complex Y. Among the following options, which statement(s) is(are) correct?

1. AAddition of silver nitrate to Y gives only two equivalents of silver chloride
2. BThe hybridization of the central metal ion in Y is d²sp³
3. CZ is a tetrahedral complex
4. DWhen X and Z are in equilibrium at 0°C, the colour of the solution is pink