5. A solid compound X is transformed into Y when it is heated at 75C. A sample of X that is quickly heated to 90C for a very short time (there is no significant decomposition) and then quenched to room tempera- ture is later found to be converted to Y at a rate that is 2.5 times that when an untreated sample of X when both are heated at 75C for a long period of time. Explain these observations