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Chemical Kinetics — Chemistry STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceChemistryChemical Kinetics1 Mark
MCQ
The maximum value of activation energy is equal to:
  • A
    Zero
  • B
    Heat of reaction
  • C
    Threshold energy
  • D
    None of these
✓

Answer

  1. None of these

Explanation:

Activation energy may be greater than heat of reaction or lesser than threshold energy.

At room temperature, most of the molecules have less than the threshold value.

Hence, if energy is supplied to the reactant molecules in the form of light or heat, they absorb that energy and reach a higher energy level which is equal to or greater than the threshold energy level, is called as activation energy.

Activation energy (Ea​) = Threshold energy - Average kinetic energy of molecules

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