Question

Calculate the entropy change in surroundings when 1 mol^-1 of H₂O_(I) is formed under standard conditions. Given ∆H = – 286 kJ mol^-1

Answer 1

q_rev = (-Δ_fH^⊖) = -286 KJ mol^-1 = 286000 J mol^-1

ΔS_{(surroundings)} = q_rev / T 

= (286000 J mol^-1) / 298 K

= 959 J K^-1  mol^-1