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NEETChemistryChemical Kinetics

Consider the decomposition of gaseous ammonia on a hot platinum surface at high pressure. Which of the following graphical plots correctly represents the kinetics of this reaction?

Options

  1. AA plot of reaction rate versus [NH₃] is a horizontal line parallel to the concentration axis.
  2. BA plot of reaction rate versus [NH₃] is a straight line passing through the origin.
  3. CA plot of half-life ( t_ 1/2 ) versus initial concentration ( [NH₃]₀ ) is a horizontal line parallel to the co
  4. DA plot of [NH₃] versus time is a straight line with a negative slope.

Correct answer

A. A plot of reaction rate versus [NH₃] is a horizontal line parallel to the concentration axis.

Step-by-step solution

The decomposition of gaseous ammonia on a hot platinum surface at high pressure is a classic example of a zero-order reaction. For a zero-order reaction, the rate law is given by: Rate = k[NH₃]^0 = k This means the rate of the reaction is constant and independent of the concentration of the reactant. Therefore, a plot of reaction rate versus [NH₃] will be a horizontal line parallel to the concentration axis. The other options describe characteristics of a first-order reaction (where rate is directly proportional to

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