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Derive an expression to calculate time required for completion of zero order reaction. - Chemistry

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Question

Derive an expression to calculate time required for completion of zero order reaction.

Short Note

Solution

Consider a reaction,

R → Pt = 0

Here R is the reactant and P is the product.

Rate = k[R]0 t = t

`(–dR)/dt` = k , dR = – kdt .....(Instantaneous rate)

On integrating both sides,

`intDr = -k intdt`

[R] = – kt + I

At t = 0,

[R] = [R0] which makes I = R0[R] = [R0] – kt.  .......(i)

Here [R] = concentration of reactant at time ‘t’.

[R0] = initial concentration of the reactant.

This reaction is known as the integrated rate equation of zero order.

After completion of zero order reaction [R] = 0

Using [R] = 0 in (i)

[R0] = kt

∴ t = `([R_0])/k`

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Chapter 4: Chemical Kinetics - Exercises [Page 55]

APPEARS IN

NCERT Exemplar Chemistry [English] Class 12
Chapter 4 Chemical Kinetics
Exercises | Q III. 38. | Page 55

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