Paper 3 · reaction kinetics
The graph shows the decomposition of cyclopropane to propene. Which statement is correct?
Arate = k[cyclopropane]
Breaction is second order with respect to cyclopropane
Crate of reaction can be followed using colour change
Dhalf-life is 10 seconds
Explanation: The marking scheme gives answer A. The graph shows exponential decay of concentration with time, with a constant half-life, indicating first order kinetics. Rate = k[cyclopropane].
ZIMSEC Chemistry Paper 3, November 2009, Q12
