Answer:
The average rate of change of 'C' with 't' is -0.1. Negative sign means there is decrease in concentration with time.
Step-by-step explanation:
Given:
Initial concentration (C₁) = 0.9
Final concentration (C₂) = 0.1
Starting time (t₁) = 0
End time (t₂) = 8
Now, change in concentration is equal to the difference of final and initial concentration. Therefore,
[tex]\Delta C=C_2-C_1\\\\\Delta C=0.1-0.9=-0.8[/tex]
Change in time interval is given as:
[tex]\Delta t=t_2-t_1=8-0=8[/tex]
Average rate of change of concentration 'C' with time 't' is given as:
[tex]R=\frac{\Delta C}{\Delta t}\\\\R=\frac{-0.8}{8}\\\\R=-0.1[/tex]
Therefore, the average rate of change of 'C' with 't' is -0.1. Negative sign means there is decrease in concentration with time.