Chemical reactions and catalysts. A chemical reaction involves a chemical change, which happens when two or more particles (which can be molecules, atoms or ions) interact. For example, when iron and oxygen react, they change to a new substance, iron oxide (rust).
It's important for parents to start weaning babies from bottles around the end of the first year and start getting them comfortable drinking from cups. The longer parents wait to start the transition, the more attached kids become to their bottles and the more difficult it can be to break the bottle habit.
Weaning is not simply a matter of getting a kitten to eat solid food. It's an important time when the kitten begins to assert its independence from its mother. This needs to be a gradual process. For the most part, my babies still nurse at 9 and 10 weeks, and sometime beyond, says Rosi Carroll of Bengals by RoJon.