JEE Advanced 2022 · Paper 1

2 mol of Hg(g) is combusted in a fixed volume bomb calorimeter with excess of O₂ at 298 K and 1 atm into HgO(s). During the reaction, temperature increases from 298.0 K to 312.8 K. If heat capacity of the bomb calorimeter and enthalpy of formation of Hg(g) are 20.00 kJ K⁻¹ and 61.32 kJ mol⁻¹ at 298 K, respectively, the calculated standard molar enthalpy of formation of HgO(s) at 298 K is X kJ mol⁻¹. The value of |X| is _______. [Given: Gas constant R = 8.3 J K⁻¹ mol⁻¹]

A solution is prepared by mixing 0.01 mol each of H₂CO₃, NaHCO₃, Na₂CO₃, and NaOH in 100 mL of water. pH of the resulting solution is _______. [Given: pKa₁ and pKa₂ of H₂CO₃ are 6.37 and 10.32, respectively; log 2 = 0.30]

The treatment of an aqueous solution of 3.74 g of Cu(NO₃)₂ with excess KI results in a brown solution along with the formation of a precipitate. Passing H₂S through this brown solution gives another precipitate X. The amount of X (in g) is ________. [Given: Atomic mass of H = 1, N = 14, O = 16, S = 32, K = 39, Cu = 63, I = 127]

Dissolving 1.24 g of white phosphorous in boiling NaOH solution in an inert atmosphere gives a gas Q. The amount of CuSO₄ (in g) required to completely consume the gas Q is _______. [Given: Atomic mass of H = 1, O = 16, Na = 23, P = 31, S = 32, Cu = 63]