CBSE Class 12 · 2006 · Delhi Compartment; also All India 2004 · Chemical KineticsVery Short Answer

What is meant by an elementary step in a reaction?

Answer: A step that occurs in a single stage, exactly as written, with no intermediates.

Solution

An elementary step is a reaction (or a step of a mechanism) that takes place in a single stage through one transition state — the molecules react exactly as the equation shows, without any detectable intermediate. Its molecularity is defined and equals the number of colliding species.

CBSE Class 12 Board · 2006 · Delhi Compartment; also All India 2004 · Subjective

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