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Why are reactions of overall order greater than three very uncommon?
- Equilibrium shifts toward reactants because of elastic collisions
- Active species are lost during collisions
- The chance of all the reacting species colliding simultaneously is very small
- Entropy and activation energy increase as more molecules are involved
Correct answer: The chance of all the reacting species colliding simultaneously is very small
Solution
A high-order elementary step would require many molecules to collide at exactly the same time, which is extremely improbable, so such reactions are rare.
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