subject

Bond Enthalpy

Chemistry ⇒ Thermochemistry and Energetics

Bond Enthalpy starts at 11 and continues till grade 12. QuestionsToday has an evolving set of questions to continuously challenge students so that their knowledge grows in Bond Enthalpy. How you perform is determined by your score and the time you take. When you play a quiz, your answers are evaluated in concept instead of actual words and definitions used.
See sample questions for grade 11
Calculate the enthalpy change for the reaction: H2(g) + Cl2(g) → 2HCl(g), given the following bond enthalpies: H–H = 436 kJ mol–1, Cl–Cl = 243 kJ mol–1, H–Cl = 431 kJ mol–1.
Describe how bond enthalpy data can be used to estimate the enthalpy change of a chemical reaction.
Describe one limitation of using average bond enthalpies to calculate enthalpy changes of reactions.
Describe the difference between bond enthalpy and lattice enthalpy.
Describe the relationship between bond length and bond enthalpy.
Explain why bond enthalpy values are usually given as average values.
Explain why the bond enthalpy of F–F is lower than that of Cl–Cl, even though fluorine is more electronegative.
Explain why the bond enthalpy of the O–H bond in water is different from that in hydrogen peroxide.
Explain why the enthalpy change for a reaction calculated using bond enthalpy values may differ from the experimental value.
Given the following bond enthalpies: C–H = 413 kJ mol–1, Cl–Cl = 243 kJ mol–1, C–Cl = 338 kJ mol–1, calculate the enthalpy change for the reaction: CH4(g) + Cl2(g) → CH3Cl(g) + HCl(g). Assume H–Cl = 431 kJ mol–1.
Given the following bond enthalpies: C–H = 413 kJ mol–1, O=O = 498 kJ mol–1, C=O = 799 kJ mol–1, calculate the enthalpy change for the reaction: CH4(g) + 2O2(g) → CO2(g) + 2H2O(g). Assume O–H = 463 kJ mol–1.
Given the following bond enthalpies: C–H = 413 kJ mol–1, O=O = 498 kJ mol–1, C=O = 799 kJ mol–1, O–H = 463 kJ mol–1. Calculate the enthalpy change for the reaction: CH3OH(g) + 3/2 O2(g) → CO2(g) + 2H2O(g).
Given the following bond enthalpies: H–H = 436 kJ mol–1, Br–Br = 193 kJ mol–1, H–Br = 366 kJ mol–1. Calculate the enthalpy change for the reaction: H2(g) + Br2(g) → 2HBr(g).
Given the following bond enthalpies: H–H = 436 kJ mol–1, O=O = 498 kJ mol–1, O–H = 463 kJ mol–1. Calculate the enthalpy change for the reaction: 2H2(g) + O2(g) → 2H2O(g).
The average bond enthalpy of the O–H bond in water is approximately 463 kJ mol–1. What does this value represent?
The bond enthalpy of a C–Cl bond is 338 kJ mol–1. Is breaking this bond an endothermic or exothermic process?
Consider the following reaction: C2H4(g) + H2(g) → C2H6(g) Given the average bond enthalpies: C=C = 612 kJ mol–1, C–C = 348 kJ mol–1, C–H = 413 kJ mol–1, H–H = 436 kJ mol–1. Calculate the enthalpy change for the reaction.
Describe how resonance structures in a molecule can affect the calculation of enthalpy change using average bond enthalpies.
Explain why the bond enthalpy of the C–O bond in carbon dioxide (CO2) is different from the C–O bond enthalpy in methanol (CH3OH).
Given the following average bond enthalpies: N–H = 391 kJ mol–1, H–H = 436 kJ mol–1, N≡N = 945 kJ mol–1. Calculate the enthalpy change for the reaction: N2(g) + 3H2(g) → 2NH3(g).