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Question 1 A B C D CH4 + 2O2 → CO2 + 2H2O This reaction is endothermic energetic C exothermic D enthalpy

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Question 2 A B C D An enthalpy change is a heat energy change at constant P B heat energy change at 298 K and 100 kPa C energy change at constant P and T D energy change at 298 K and 100 kPa

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Question 3 A B C D What type of reaction is this? equilibrium exothermic C enthalpy D endothermic

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Question 4 0.1g of methane was completely burnt, and heated up 100g of water by 5.0K. What was the heat energy change? A -2.1J B -210J C -2100J D -21J

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Question 5 0.1g of methane was completely burnt, and gave out 2100J. What is the enthalpy change? A -336kJ B -13.13kJ C -13.13J D -336J

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The enthalpy of formation for ammonia is given by Question 6 The enthalpy of formation for ammonia is given by A N2+3H2→2NH3 B N2 + H2→NH3 C N+3H→NH3 D N2 (g)+ H2(g)→NH3(g)

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Question 7 A B C D To work out ΔH for the combustion reaction, CH4 + 2O2 → CO2 + 2H2O using enthalpy of formation values: A Δproduct - Δreactant B ΣΔproduct - ΣΔreactant C Δreactant - Δproduct D ΣΔreactant - ΣΔproduct

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Question 8 A B C D ΔHformation of O2(g) is 2 x ΔHformation O(g) 16 D O(g) + O(g) → O2(g)

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Question 9 A B C D Bond breaking is usually exothermic usually endothermic C always exothermic D always endothermic

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Mean bond dissociation enthalpies are Question 10 Mean bond dissociation enthalpies are A always negative B averaged over many compounds C Zero for elements D approximate values

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Understand that reactions are either exothermic or endothermic and apply the sign convention Define the term “enthalpy change”, recall what standard conditions are and understand that conditions affect enthalpy changes Define activation energy and relate it to bond breaking Recall and use q = mc∆T and ∆H = q/n and explain how simple enthalpy changes are measured  Use bond dissociation enthalpy data to calculate approximate enthalpy changes and vice versa  Define Hess' Law, standard enthalpy of formation and standard enthalpy of combustion Calculate enthalpy changes from enthalpy of formation data using Hess' Law and vice versa Calculate enthalpy changes from enthalpy of combustion data using Hess' Law and vice versa