CBSE Class 12 · 2008 · Delhi · Chemical KineticsShort Answer

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What is meant by the 'rate constant, k' of a reaction? If concentration is expressed in mol L and time in seconds, what would be the units of k (i) for a zero order reaction and (ii) for a first order reaction?

Answer: k = rate when every reactant concentration is unity. (i) mol L⁻¹ s⁻¹ (ii) s⁻¹

Solution

The rate constant is the rate of the reaction when the molar concentration of each reactant is unity; it is fixed for a reaction at a given temperature.
Units ():
(i) zero order: mol L s
(ii) first order: s

CBSE Class 12 Board · 2008 · Delhi · Subjective

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