Given that the half-life of the reaction is 50 min at a particular concentration and it becomes 100 min when the concentration of reactants is doubled, we can analyze the relationship between concentration and half-life to determine the order of the reaction.
For a zero-order reaction, the half-life is directly proportional to the initial concentration. If doubling the concentration leads to a doubling of the half-life, it indicates a zero-order reaction. However, in this case, doubling the concentration results in the half-life remaining the same (100 min), not doubling. Therefore, the reaction is not zero order.
For a first-order reaction, the half-life is independent of the initial concentration. Doubling the concentration should not have any effect on the half-life. However, in this case, doubling the concentration causes the half-life to increase from 50 min to 100 min. Therefore, the reaction is not first order.
For a second-order reaction, the half-life is inversely proportional to the square of the initial concentration. Doubling the concentration should result in the half-life being reduced by a factor of four. However, in this case, doubling the concentration causes the half-life to double. Therefore, the reaction is not second order.
For a third-order reaction, the half-life is inversely proportional to the cube of the initial concentration. Doubling the concentration should result in the half-life being reduced by a factor of eight. However, in this case, doubling the concentration causes the half-life to double. Therefore, the reaction is not third order.
Based on the analysis, the correct answer is (1) Zero order. |
