Final answer:
The reaction rate for a zero-order reaction remains constant regardless of changes in the concentration of the reactant. Since the initial rate is 0.0200 m/s for [A] = 0.100 m, increasing [A] to 0.400 m does not affect the rate; it remains at 0.0200 m/s.
Step-by-step explanation:
The student's question involves calculating a new reaction rate when the concentration of a reactant [A] increases. Initially, if the rate = k[A]0, where k is the rate constant and [A] is the concentration, this implies that the reaction rate is zero-order with respect to [A]. A zero-order reaction means that changing the concentration of [A] does not affect the rate.Since the rate is initially given as 0.0200 m/s when [A] = 0.100 m, and the reaction is zero-order with respect to [A], when the concentration of [A] is increased to 0.400 m, the rate remains the same. Therefore, the new reaction rate is also 0.0200 m/s.