Covalent Bonds

Covalent Bonds

• Covalent bonds occur when atoms share electrons.

• Covalent bonds generally form between nonmetals.

• Atoms that are covalently bonded form molecules.

Covalent Bonds

• Covalent bonds occur at unpaired valence electrons on the outer shell for each atom.

• Example: H2O has 2 bonds:

Before… After…

H O H O HH

Covalent Bonds

• Covalent bonds create neutral molecules when they come together.

• How many bonds between 2 atoms?– Covalently bonded atoms can bond

up to 3 times. They cannot exceed 3 bonds between two atoms.

Covalent Bonds

• Double bonds: When two atoms share two pairs of electrons. – EX: O2

• Triple bonds: When two atoms share three pairs of electrons. – EX: N2

Covalent Bonds

• Properties of Covalent Bonds:– Low melting points– Low boiling points– Poor conductor of electricity– Between nonmetals and nonmetals