Gasoline is a mixture of the alkanes and unlike many chemicals, can be stored for long periods and transported without problem. It is only when ignited that it has enough energy to continue reacting. This property makes it difficult for alkanes to be converted into other types of organic molecules.
Recovery from being spayed is usually around 10 days. My kitten was back to her usual self in three days but it took 10 days for the incision to heal enough for the stitches to come out.
The mother cat can be spayed as soon as the kittens are weaned, usually when they around 10 to 12 weeks old. Some shelters will have their kittens neutered at 8 weeks - 12 weeks or 2.0 lbs also. Neutering does not make cats fat or change their personalities regardless of when it's done.