Cyclopropane rearranges to form propene
`to CH_(3) - CH = CH_(2)`
This follows first order kinetics. The rate constant is `2.714 xx 10^(-3) sec^(-1)`. The unitial concentration of cyclopropane is 0.29 M. What will be the concentraion of cyclopropane after 100 sec?

Options

A. 0.035 M
B. 0.22 M
C. 0.145 M
D. 0.0018 M

Answer

B

Explanation

`k = (2.303)/(t) "log" (a)/((a - x))`
(a - x) is the concentration left after 100 sec.
`2.7 xx 10^(-3) = (2.303)/(100) "log" (0.29)/((a - x))`
`implies (0.27)/(2.303) = "log" (0.29)/((a -x)) implies 0.117 = "log" (0.29)/((a - x))`
`implies (a - x) = 0.22 M`