The question is missing the table. Here is the complete question.
The tableshows the concentration of a reactant in the mixture over a period of time.
Reactant Concentration
Time (s) Concentration (M)
0 1.8
210 1.2
450 0.8
580 0.6
720 0.4
What is the average rate of reaction over the first 450 seconds?
A. 1.6x M
B. 1.9x M
C. 2.0x M
D. 2.2x M
Answer: D. 2.2x M
Explanation: The average rate of a reaction is the rate of change of the concentrations (of reactants or products) in a period of time:
average = - ΔC/Δt
In this case, concentration is negative because it's related to reactant, since its concentration dimishes while the concentration of product increases.
For the first 450 seconds:
Average =
Average =
Average = 0.0022
or
Average = 2.2x
So, <u>the Average Rate of the reaction is 2.2x</u><u>M</u>