The chemicals have to be in contact with each other in order for any type of chemical reaction to take place. One of the most common examples of a chemical reaction is the rusting of a fence. The combining of the metal and the oxygen causes bonds to break and new ones to be created, which results in the creation of iron oxide or rust.
The ear canal cleans itself with a waxy secretion called cerumen. Cerumen is resistant to water, sticky (to trap dust) and migrates out of the ear canal to self-clean the ear. Sometimes, the wax builds up and causes symptoms, including mild deafness and a sensation of fullness inside the ear.
Earwax, also known as cerumen, is a yellowish waxy substance secreted in the ear canal of humans and other mammals. It protects the skin of the human ear canal, assists in cleaning and lubrication, and also provides some protection from bacteria, fungi, insects and water. Earwax consists of shed skin cells, hair, and the secretions of the ceruminous and sebaceous glands of the outside ear canal. Major components of earwax are long chain fatty acids, both saturated and unsaturated, alcohols, squalene, and cholesterol. Excess or compacted cerumen can press against the eardrum or block the outside ear canal or hearing aids, potentially causing hearing loss.