R1 Reactivity 1: What drives chemical reactions?

Practice questions on Reactivity 1: What drives chemical reactions?

• Explain why the reaction CH₄(g) + 2O₂(g) → CO₂(g) + 2H₂O(g) is spontaneous at all temperat… (4 marks, Explain)
• Explain why the dissolution of ammonium nitrate in water, a process that is endothermic, i… (4 marks, Explain)
• Explain why the energy density of ethanol (C₂H₅OH) is lower than that of octane (C₈H₁₈) wh… (4 marks, Explain)
• Explain why the use of hydrogen as a fuel is considered environmentally advantageous compa… (4 marks, Explain)
• Explain why the Born–Haber cycle for potassium fluoride gives a value for lattice enthalpy… (4 marks, Explain)
• Explain why the standard enthalpy of atomisation of chlorine is exactly half the bond enth… (4 marks, Explain)
• Explain why the lattice enthalpy of magnesium oxide is significantly greater in magnitude … (4 marks, Explain)
• Explain why the standard enthalpy change of combustion of propan-1-ol is more negative tha… (4 marks, Explain)
• A student dissolves 4.00 g of anhydrous copper(II) sulfate in 50.0 cm³ of water and measur… (4 marks, Explain)
• Explain why the electron affinity of oxygen has two values — a first electron affinity tha… (4 marks, Explain)
• Explain why the enthalpy change of neutralisation for the reaction between ethanoic acid a… (4 marks, Explain)
• Explain why Hess's law is used to determine the standard enthalpy change of formation of e… (4 marks, Explain)
• Explain why the experimentally determined enthalpy change of combustion of ethanol, measur… (4 marks, Explain)
• Explain why the standard enthalpy of combustion of methane is more exothermic per mole tha… (4 marks, Explain)
• Explain why the enthalpy change of combustion of a fuel determined by a simple calorimetry… (4 marks, Explain)
• Explain why the enthalpy change of combustion per gram of hydrogen (H₂) is significantly g… (4 marks, Explain)
• Explain why the reaction of nitrogen gas with oxygen gas to form nitrogen monoxide, N₂(g) … (4 marks, Explain)
• Explain why the reaction 2SO₂(g) + O₂(g) → 2SO₃(g) is spontaneous at low temperatures but … (4 marks, Explain)
• Explain why the decomposition of calcium carbonate, CaCO₃(s) → CaO(s) + CO₂(g), is non-spo… (4 marks, Explain)