Last seen: Oct 19, 2020
(c) If the Assertion is correct but Reason is incorrect. Explanation: The temperature of a gas decreases when it undergoes adiabatic expansion.
(b) If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion. Explanation: Entropy is defined as the exte...
(e) If the Assertion is incorrect but the Reason is correct. Explanation: Ionic reactions are spontaneous as oppositely charged ions exert stronge...
(b) 41.2 Explanation: ΔH = Σ[ΔfH° products] - Σ[ΔfH° reactants] ΔH° = [ΔfH°(CO)(g) + ΔfH°(H2O)(g) - [ΔfH°(CO2 (g) + ΔfH°H2 (g)] = [-110.5 + (-...
(c) 2.4 K Explanation: Given CP = 75 JK-1 mol-1 n = 100/18 mole, Q = 1000 J, ΔT = ? Q = nCPΔT => ΔT = (1000 x 18)/(100 x 75) = 2.4 K
(b) +48 Explanation: C6H6(l) + 15/2O2(g) → 6CO2(g) + 3H2O(l) ΔH = -3270 kJ mol-1 ....(i) C(gr) + O2(g) → CO2(g) ΔH = -394 kJ mol-1 ....
(b) C2H4(g) + H2(g) → C2H6(g) Explanation: ΔH is given by ΔH = ΔU + ΔngRT When Δng = 0, ΔH = ΔU When Δng ≠ 0, ΔH ≠ ΔU For C2H4(g) + H2(g) ...
(a) +16.8 kJ mol-1 Explanation: I2(s) + Cl2(g) → 2ICl(g) ΔrH = [ΔH(I2(s) → I2(g)) + ΔHI-I + ΔHCl-Cl] - [ΔHI-Cl] = 151.0 + 242.3 + 62.76 - 2 × ...
(b) –, +, – Explanation: For combustion reaction, ΔH is negative, Δn = (16 + 18) - (25 + 2) = +7, so ΔS is +ve, reaction is spontaneous, hence Δ...
(a) -196 kJ/mol Explanation: 2H2O2(l) → 2H2O(l) + O2(g) DH = ? DH = [2' DHf of H2O(l) + (DHf of O2(g)) - (2' DHf of H2O2(l))] = [(2 x -286) + ...
(b) 41.2 Explanation: ΔH = ΔH°f (products) - ΔH°f (reactants) = –110.5 + (-241.8) - (-393.5+0) = 41.2 kJ
(d) ΔH = –ve, TΔS = + ve at any temperature
(d) 400 kJ mol-1 Explanation: Let bond energy of A2 be x then bond energy of AB is also x and bond energy of B2 is x/2. Enthalpy of formation of...
(a) -840 k cal mol-1 Explanation: ΔHc (C2H6) - ΔHc(CH4) = -368.2 - (-210.8) = -157.4 ΔHc (C3H8) - ΔHc (C2H6) = -526.2 - (-368.4) = -157.8 ...
(c) NH3(g) + HCl(g)→ NH4Cl(s)
(a) HCl is more stable than HF Explanation: More the enthalpy of formation less will be the stability of the compound.
(b) 150 K Explanation: Since the gas expands adiabatically (i.e., no change in enthalpy) so the heat is totally converted into work. For the ga...
(c) –, – Explanation: 2Cl(g) → Cl2 (g) Entropy is decreasing (–ve) in the reaction. Further the reaction is exothermic since a bond is being for...
(b) zero Explanation: Change in internal energy (ΔE) is zero during isothermal expansion of a gas.
(b) -121 kJ/mol Explanation: The required reaction is C6H10+ H2 → C6H12, ΔH1 = ? ....(1) Let us write the given facts H2 + 1/2O2 → H2O; ...