Karnataka Board PUCPUC Science 2nd PUC Class 12

For a Chemical Reaction R → P, the Variation in the Concentration (R) Vs. Time (T) Plot is Given as - Chemistry

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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.

(iii) Write the unit of rate constant for this reaction.

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Solution 1

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

Solution 2

(i) The variation in the concentration (R) vs. time (t) plot shown here represents a zero order reaction, for which the rate of the reaction is proportional to zero power of the concentration of the reactants.

(ii) For a zero order reaction, rate constant is given as

`k=([R]_0-[R])/t`

So, the slope of the curve for the variation in the concentration (R) vs. time (t) plot is equal to the negative of the rate constant for the reaction.

Solution 3

(iii) Since it is a first order reaction, the unit of the rate constant is s−1.

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2013-2014 (March) All India Set 1

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