For A products, time and concentration data were collected and plotted as shown here

For A products, time and concentration data were collected and plotted as shown here. Determine the reaction order, the rate constant, and the units of the rate constant.

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Concepts and reason
This problem is based on the concept of rate of reaction and order of a reaction. Rate of reaction is defined as the rate of disappearance of reactants or rate of appearance of products with change in time. The order of a reaction is the number of reactant molecules taking part in the reaction.

Fundamentals
Consider a hypothetical reversible reaction:
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Rate of reaction for the above reaction is given as follows:


number of moles of B, c is the number of moles of C, d is the number of moles of D.

According to the Rate law, rate of the above reaction can also be given as:
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Order of the reaction is the sum of the powers of the concentration of the reactants.
Therefore, the order of the reaction is a + b.

Answer:

A
The given reaction is as follows:
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Since the plot of [A] Vs time gives the straight line, the given reaction is a zero order reaction.

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B
Initial concentration, image = 0.700 M
Concentration of A after 30 secs, image = 0.662 M
According to zero order reaction, rate constant is given as follows:
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