alleryStart learning →What is the minimum amount of energy that must be supplied before a chemical reaction will start?
ABond length value
BEnthalpy of system
CKinetic energy sum
DActivation energy
Answer & Solution
Correct answer: D. Activation energy
1. A match does not light while it is waved in the air; it has to be struck first.
2. Activation energy is the minimum amount of energy needed to start a chemical reaction.
3. It is measured as the gap between the energy of the reactants and the peak of the energy curve.
4. An enzyme is a catalyst that speeds a reaction up by lowering this activation energy.
_Source: Siyavula Physical Sciences Grade 11 (Everything Science, CC BY 4.0), Chapter 12: Energy and chemical change_
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