Final answer:
The initial rate of a reaction can be determined by the slope of the best-fit line at t = 0 on a concentration versus time plot. The correct answer is B).
Step-by-step explanation:
The best-fit line for the plot of concentration [B] versus time allows you to determine the initial rate of a reaction, which is not the final rate (A), average rate (B), or maximum rate (D) of the reaction. Instead, the initial rate can be determined from the slope of the line (C) at the beginning of the reaction.
At the start of a reaction, the initial rate is typically the fastest because the concentrations of reactants are at their highest. Over time, the reaction rates generally decrease as reactant concentrations decrease. By measuring the concentration of reactants or products over time and plotting these data points.
A line can be drawn to represent the reaction's progress. When determining reaction rates, it is important to remember that chemists express rates as positive numbers; therefore, a negative sign is used in the calculation to convert the slope into a positive rate value when dealing with the depletion of reactants.