Practice Bond Enthalpies (4.3) - Chapter 4: Energetics/Thermochemistry

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6 sample questions

Question 1.
What is bond enthalpy?
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Think about the energy required to disrupt chemical connections.
Question 2.
In an exothermic reaction, what happens to energy?
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Relate to the temperature change observed.
3Question 3.
What is the bond enthalpy of a C-H bond approximately?
- 414 kJ/mol
- 498 kJ/mol
- 963 kJ/mol
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Recall the values for common bonds.
4Question 4.
True or False: Bond enthalpy values are exact for every molecule.
- True
- False
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Think about the variation in chemical environments.
Question 5.
Predict the enthalpy change for the reaction: C2H4(g) + H2(g) → C2H6(g). Given: C=C = 612 kJ/mol, C-H = 414 kJ/mol. Calculate using bond enthalpies.
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Set up your energy values carefully and watch your signs!
Question 6.
Discuss how factors like bond order influence reactions with an example, particularly focusing on C-H vs C=C bonds in terms of stability and energy.
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Consider the physical attributes of the bonds when constructing your example.

4 more questions in this section. Enroll free to practise them all.