Biology 1001A Lecture : BIOLOGY LECTURE 2.docx
Document Summary
Water is a polar molecule while oils, fatty acids and lipids are nonpolar. This is what causes oil to not to mix with water. A water molecule is composed of one oxygen molecule and two hydrogen molecule while oil is a hydrocarbon and is composed of carbon and hydrogen molecule. Since oxygen has a high electronegativity it attracts the electrons away from the hydrogen which makes oxygen slightly negative and hydrogen slightly positive. This is what makes the water molecule polar. Unlike oxygen, carbon is not very electronegative and so doesn"t attract the electrons from hydrogen and so the oil is nonpolar. The polarity of the water cause mutual attraction between the water molecules forming hydrogen bonds between them. Also the hydrocarbon molecules are pushed out of the way as the water molecule forms intermolecular bonds and thus separating the oil from the aqueous solution. Primarily from animal fats (some plant fats as well).