Moderate

For 3rd order reaction, the half life is inversely proportional to initial concentration of reactants

Correct answer: B. Square

  • A. Single
  • B. Square
  • C. Cube
  • D. (d) Raise to power four

Explanation

For a 3rd order reaction, the relationship between the half-life and the initial concentration of reactants is:(b) SquareThe half-life of a 3rd order reaction is inversely proportional to the square of the initial concentration of the reactants. In general, for nth order reactions, the relationship between half-life and initial concentration is specific to the order of the reaction. For a 3rd order reaction, the relationship is that the half-life is inversely proportional to the square of the initial concentration.(a) Single:This statement suggests that for a 3rd order reaction, the half-life is inversely proportional to the initial concentration of reactants raised to the power of one (single). However, this is not accurate for a 3rd order reaction. In a 3rd order reaction, the relationship between the half-life and the initial concentration of reactants is not linear; it's related to the square of the initial concentration, not to the initial concentration itself.(c) Cube:This statement proposes that for a 3rd order reaction, the half-life is inversely proportional to the initial concentration of reactants raised to the power of three (cube). However, this is also incorrect for a 3rd order reaction. The relationship between the half-life and the initial concentration of reactants in a 3rd order reaction is not cubic. It's related to the square of the initial concentration, not the cube.(d) Raise to power four:This option suggests that for a 3rd order reaction, the half-life is inversely proportional to the initial concentration of reactants raised to the power of four. This is not accurate for a 3rd order reaction. The relationship between the half-life and the initial concentration of reactants in a 3rd order reaction is not to the power of four. It's related to the square of the initial concentration, not the fourth power.

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