PHYSICAL CHEMISTRY IN BRIEF

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CHAP. 9: CHEMICAL KINETICS [CONTENTS] 274

Obr.9.2:Time dependence of the reactants concentration for a first-order reaction of the type A→B.
The initial concentration of the reactant iscA0, the starting concentration of the product is zero.


Solution
We calculate the rate constant using equation (9.26)

k=

ln 2
τ 1 / 2

=

0. 693

693

= 0. 001 s−^1.

The concentration at timeτ= 5 min is calculated from relation (9.25)

cA= 0.1 exp (− 0. 001 ·300) = 0. 074 mol dm−^3.

9.2.3 Second-order reactions


We will deal with three types of second-order reactions:
a) Type
2 A→products. (9.27)

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