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प्रश्न
For a chemical reaction R → P, the variation in the concentration (R) vs. time (t) plot is given as:
(i) Predict the order of the reaction.
(ii) What is the slope of the curve?
(iii) Write the unit of rate constant for this reaction.
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उत्तर १
For a chemical reaction R→P, the variation in the concentration (R) vs. time (t) plot is given as follows:
(i) The order of the reaction zero.
(ii) Slope = -k
उत्तर २
(i) Predict the order of the reaction
The graph shows a straight line when concentration of reactant R is plotted against time t.
[R] = [R]0 − kt
Since the plot is a straight line with a negative slope, the reaction is zero order.
(ii) Slope of the curve
From the zero-order equation:
[R] = [R]0 − kt
The slope of the [R] vs t graph is −k (negative of the rate constant).
(iii) Unit of rate constant
For a zero-order reaction:
Rate = k
Rate has units of concentration/time.
If concentration is in mol L−1 and time in seconds:
Unit of k = mol L−1s−1
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