Govt Exams
ΔTf = Kf × m × i. Moles of NaCl = 2.3/58.5 = 0.0394 mol, m = 0.0394/0.1 = 0.394 m, i = 2 (dissociates into Na⁺ and Cl⁻). ΔTf = 5.12 × 0.394 × 2 ≈ 4.04 K (closest is 3.92 K).
Order can be determined using integrated rate law (straight line plot), differential rate law (initial rate method), and half-life method (for special cases).
E°cell = E°cathode - E°anode = 0.34 - (-0.76) = 1.10 V. Cu is cathode (reduction), Zn is anode (oxidation).
κ = Λₘ × C = 426 × 0.01 = 4.26 S/cm. This needs conversion: κ = 4.26 × 10⁻² S/cm = 0.426 S/cm. Molar conductivity doesn't change; conductivity does.
Increasing pressure favours the direction with fewer moles of gas. For 2NO₂ ⇌ N₂O₄, it favours forward reaction (correct), but statement A is incomplete without specifying the reaction.
For this reaction, Δn = 1 - 2 = -1, so Kp = Kc(RT)^Δn = Kc(RT)⁻¹ = Kc/(RT).
ΔG° = -nFE°cell. For n=2 (typical): ΔG° = -2 × 96500 × 0.34 = -65,620 J/mol ≈ -65.6 kJ/mol.
Osmotic pressure: π = CRT where C is molar concentration. It's a colligative property dependent on number of solute particles.
Henry's law constant for CO₂ in water at 25°C is Kh ≈ 1.67 × 10³ atm·L/mol, used as P = Kh·x.
For isothermal process: W = nRT ln(Vf/Vi). Since Vf > Vi, work done by gas is positive.