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For the reaction A -> P, match the order of reaction (Column I) with kinetic properties (Column II) and additional features (Column III), then identify the INCORRECT combination. Column I: (I) First Order, (II) Second Order, (III) Third Order, (IV) Zero Order. Column II: (i) reaction complete in finite time, (ii) reaction complete in infinite time, (iii) half life independent of reactant concentration, (iv) half life decreases as reactant concentration increases. Column III: (P) rate depends on concentration, (Q) reactant concentrations at equal time intervals form a G.P., (R) reactant concentrations at equal time intervals form an A.P., (S) half life depends on temperature.

1. (II), (ii), (P)
2. (IV), (iii), (R)
3. (III), (ii), (P)
4. (I), (ii), (Q)

Correct answer: (IV), (iii), (R)

Solution

For zero order, half-life t(1/2) = [A]0/(2k) depends on concentration, so pairing (IV) with (iii) 'half life independent of concentration' is wrong. Also zero order completes in finite time, not infinite. Hence (IV),(iii),(R) is the incorrect combination.

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