Final answer:
The concentration of hydrogen peroxide affects the rate of the reaction, with higher concentrations typically leading to faster reaction rates. This is illustrated by examining samples of diluted and undiluted hydrogen peroxide, where undiluted samples react more quickly due to a higher number of available substrate molecules.
Step-by-step explanation:
Comparing the reaction times for diluted and straight hydrogen peroxide (H2O2) demonstrates that the concentration of the substrate does indeed affect the rate of the reaction. This phenomenon is consistent with the principles of chemical kinetics, where the concentration of a reactant is a key factor in determining the rate at which a reaction proceeds. When working with hydrogen peroxide specifically, which decomposes over time into water and oxygen, measuring the concentration at regular intervals provides data on the reaction rate.
As the concentration of H2O2 decreases, the reaction rate would typically be measured to decrease as well. This occurs because there are fewer hydrogen peroxide molecules available to decompose, thus reducing the number of effective collisions and the frequency of reaction events. In an experiment, if test tube A contains diluted hydrogen peroxide and test tube C contains undiluted hydrogen peroxide, test tube C would likely show a faster reaction rate due to higher substrate concentration. Calculations based on the rate of change of concentration over time, or graphical analysis using tangent lines on a concentration vs. time plot, can quantify the reaction rate differences between the two samples.