Question detail
In The energy change of reactions (HT only), which answer keeps the sign and unit correct for CH4 + 2O2 -> CO2 + 2H2O?
Try the question, check the answer, then read the explanation to understand the curriculum point.
At a glance
MCQ
Type
practice
Style
Topic
Exothermic and endothermic reactions
Question
- A. -814 kJ, exothermic
- B. 814 kJ, endothermic
- C. 0 kJ, no net energy change
- D. Incorrect bond-energy interpretation 4
Answer
The correct option is -814 kJ, exothermic.
Explanation
The correct option is "-814 kJ, exothermic" because it supports the approved learning objective: (HT only) Explain that bond energies can be used to calculate energy released when bonds form. The other options are incorrect or weaker because they are vague, use the wrong Chemistry context, or do not clearly explain the answer for The energy change of reactions (HT only).
Common mistake
Misunderstanding Bond Energies
Students often confuse bond energies with the overall energy change of a reaction, thinking that bond energies alone determine whether a reaction is exothermic or endothermic.
Emphasize that bond energies are used to calculate the energy released when bonds form, and this must be compared to the energy needed to break bonds to determine the overall energy change.
Related flashcards
Flashcard 1 of 5
Related practice questions
Question 1 of 5
Choose an answer, get feedback, then move sideways through the set.