HEATING OIL FACT

Organic oil is also produced by plants, animals, and other organisms through organic processes, and these oils are remarkable in their diversity. Oil is a somewhat vague term in chemistry; instead, the scientific term for oils, fats, waxes, cholesterol, and other oily substances found in living things and their secretions, are lipids. Lipids, ranging from waxes to steroids, are somewhat hard to characterise, and are united in a group almost solely based on the fact that they all repel, or refuse to dissolve in, water, and are however comfortably miscible in other liquid lipids. They also have a high carbon and hydrogen content, and are considerably lacking in oxygen compared to other organic compounds and minerals.
http://en.wikipedia.org/wiki/Oil
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