bio exam 1: molecules & chemical bonds

What is a molecule?

Two or more atoms chemically bonded together

What is a compound?

A substance containing two or more different elements chemically combined

What is a salt?

An ionic compound made of positive and negative ions

What is a covalent bond?

A bond where atoms share electrons

What is an ionic bond?

Attraction between oppositely charged ions

What is a hydrogen bond?

A weak attraction involving a partially positive hydrogen

How do water molecules attract each other?

By forming hydrogen bonds

What is electronegativity?

How strongly an atom attracts shared electrons

What is a polar covalent bond?

Electrons are shared unequally

What is a nonpolar covalent bond?

Electrons are shared equally or nearly equally

When might an atom give up electrons?

When losing electrons helps fill its outer shell

When might an atom gain electrons?

When gaining electrons fills its outer shell

When do atoms share electrons?

When sharing helps fill their outer shells