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Q.
For a zero-order reaction with rate constant $k$, the slope of the plot of reactant concentration against time is
KVPYKVPY 2013Chemical Kinetics
Solution:
For a zero order reaction,
$[R] = - kt + [R]_0$
Comparing with equation of a straight line $y = mx + c$.
The slope of plot of reactant concentration against time is - $k$.