Cyclopropane, an anesthetic, decomposes to propane.The reaction is first order with respect to cyclopropane with k = 9.2 s-1 at 1000°C.

a) Calculate the half-life of the reaction.

b) How much of a 3.00 g sample of cyclopropane remains after 0.50 sec at
1000°C?

Question

Cyclopropane, an anesthetic, decomposes to propane.The reaction is first order with respect to cyclopropane with k = 9.2 s-1 at 1000°C.

a) Calculate the half-life of the reaction.

b) How much of a 3.00 g sample of cyclopropane remains after 0.50 sec at
1000°C?

jfraser · Answer

Minor correction, but cyclopropane can't decompose into propAne, but it can decompose into propEne:

|dw:1365591661072:dw|

The formulas must be the same, so C3H6(cyclo) --> C3H6 (linear)

a) plug into the equation for determining half life when given k:$$t_{\frac{1}{2}} = \frac{\ln(2)}{k}$$

b) plug the time, k, and mass of cyclopropane into the rate law equation for a first-order reaction and solve for A_t:
$$A_t = A_0*e^{-kt}$$