Carbon disulfide, CS₂, is flammable and reacts readily with oxygen, as shown in reaction 1. reaction 1 CS₂(g) + 3O₂(g) → CO₂(g) + 2SO₂(g) Table 3.1 shows the standard enthalpy of formation, ∆H°f, and the standard entropy, S°, for some substances. Table 3.1 CS₂(g) O₂(g) CO₂(g) SO₂(g) ∆H°f / kJ mol⁻¹ 116.7 0.0 -393.5 -296.8 S° / J K⁻¹ mol⁻¹ 237.8 205.2 213.8 248.2 Calculate the standard Gibbs free energy change, ∆G°, in kJ mol⁻¹, for reaction 1 at 25°C. ∆G° = ................................... kJ mol⁻¹ [3]

1. (a)Carbon disulfide, CS₂, is flammable and reacts readily with oxygen, as shown in reaction 1. reaction 1 CS₂(g) + 3O₂(g) → CO₂(g) + 2SO₂(g) Table 3.1 shows the standard enthalpy of formation, ∆H°f, and the standard entropy, S°, for some substances. Table 3.1 CS₂(g) O₂(g) CO₂(g) SO₂(g) ∆H°f / kJ mol⁻¹ 116.7 0.0 -393.5 -296.8 S° / J K⁻¹ mol⁻¹ 237.8 205.2 213.8 248.2 Calculate the standard Gibbs free energy change, ∆G°, in kJ mol⁻¹, for reaction 1 at 25°C. ∆G° = ................................... kJ mol⁻¹ [3][3]
2. (b)Carbon disulfide reacts with chlorine to form tetrachloromethane, as shown in reaction 2. reaction 2 CS₂ + 3Cl₂ → CCl₄ + S₂Cl₂ ∆H° = −261.6 kJ mol⁻¹ ∆S° = −365.5 J K⁻¹ mol⁻¹ Calculate the maximum temperature, in K, for reaction 2 to be feasible. temperature = ................................... K [2][2]