Linearity of a Rxn

[705984992]

Why do some reactions show non-linear dependence on the reaction concentration? Why is the graph for a zeroth order linear but for a first or second order, it's not linear. What makes it not linear?

[CeeJay Chhum 1L]

The graph of [A] v time is linear in zeroth order because in zeroth order, rate = k, meaning rate is independent of [A]. Basically, this means that whatever the [A] is at, the rate or slope of the [A] v time graph will be constant.

On the other hand for first and second order, rate = k[A] and k[A]^2, respectively. This means that when we are decreasing [A] as time goes on, the rate of which [A] decreases will be ever steeper. Thus, the slope of [A] vs time is not constant and the line is not linear

[705903057]

The linearity of the concentration-time graph depends on the order of the reaction. Zeroth-order reactions exhibit linear concentration-time graphs because the rate is constant. First and second-order reactions do not show linear concentration-time graphs because their rates are dependent on the concentration of reactants, leading to exponential or reciprocal relationships between concentration and time.