Define zero order reaction. Derive integrated rate equation for rate constant of a zero order reaction.

Explanation

Zero order reaction : The reaction for which the rate of reaction does not depend upon concentration of reactants is called a zero order reaction. For such a reaction,
Rate = `k[R]^(0)=k`
Integrated rate equation for a zero order reaction : Consider a zero order reaction,

`R rarr P`
Rate= `(-d[R])/(dt)=k[R]^0=k`
or `=(-d[R])/(dt)=k`
`-d[R]=kdt=intd[R]=k int dt`
`-[R]=kt+1`
where 1 is constant of integration.
At t = 0, the concentration of reactant R=`[R]_0` where `[R]_0` is initial concentration of reactant, Substituting in equation (i)
`[R]_0 = -kxx0+I`.
or `I=[R]_0` Substituting the value of I in equation (i)
`[R]=-kt+[R]_0`
`kt=[R]_0[R]`
or `k=([R]_0-[R])/(t)`
or `[R]=-kt+[R]_0`