Unit 1: Chemistry of Life

Biology

The scientific study of life

Covalent bond

The sharing of a pair of the outermost shell valence electrons by two atoms

Molecules

Two or more atoms held together by covalent bonds

Electronegativity

An atom's attraction for the electrons of a covalent bond (like gravity)

Nonpolar covalent bond

Atoms share the electrons equally (e.g. H2)

Polar covalent bond

One atom is more electronegative, leading to partial charges (e.g. H2O)

Ionic bonds

Result from the taking or losing of an electron, creating oppositely charged ions that are attracted to each other

Cation

Positively charged ion

Anion

Negatively charged ion

Hydrogen bonds

Form when a hydrogen atom is attracted to electronegative atoms, considered weak bonds

Cohesion

Molecules staying close together because of hydrogen bonds, self-to-self stickiness

Adhesion

One substance clinging to a different substance (like tape)

Capillary Action

The ability of a liquid to flow in narrow spaces without external forces like gravity

Specific heat

The amount of heat needed to change the temperature of 1 gram of a substance by 1 degree Celsius

High specific heat

Water is very resistant to changes in temperature

Heat of vaporization

The heat needed for 1 gram of a liquid to be converted to a gas

Evaporative cooling

The process of a liquid cooling as it evaporates