Question 1 ▼ Which of the following reactions has ∆H = ∆U? C(s) + O2(g) → CO2(g) 2H2(g) + O2(g) → 2H2O(l) N2(g) + 3H2(g) → 2NH3(g) CaCO3(s) → CaO(s) + CO2(g) Check Answer Report Question
Question 2 ▼ Which of the following reactions is endothermic but spontaneous? Burning of wood Formation of water NH4NO3(s) → NH4+(aq) + NO3–(aq) Freezing of water Check Answer Report Question
Question 3 ▼ Which of the following is a spontaneous process at room temperature? Water freezing Steam condensing Ice melting Sugar dissolving in cold tea Check Answer Report Question
Question 4 ▼ Which of the following reactions has a positive ∆S? N2(g) + 3H2(g) → 2NH3(g) 2Cl(g) → Cl2(g) H2O(l) → H2O(g) CO2(g) → CO2(s) Check Answer Report Question
Question 5 ▼ 5.19 For the reaction 2A(g) + B(g) → 2D(g), ∆U° = –10.5 kJ and ∆S° = –44.1 J K–1. Is the reaction spontaneous at 298 K? Spontaneous Non-spontaneous At equilibrium Cannot be predicted Check Answer Report Question