Question

Is a molecule the same as a compound?

Answer 1

Yes and no. Molecules are compounds, but not all compounds are molecules.

Molecular compounds are those which have only covalent bonding. Examples would include compounds like methane, water, sugar, proteins, etc.

Many compounds have ionic bonding. Technically, it is incorrect to refer to molecules of ionic compounds - though many people do this. Bill Nye talked about molecules of salt in one of the "Bill Nye the Science Guy" episodes. Sorry Bill, love your shows, but in that case you were incorrect. :-(

So, what is your take home message?

Molecules are the representative particle (smallest particle which retain the properties of a substance) of covalently bonded compounds.

Formula units (lowest whole number ratio of ions) are the representative particles for ionic compounds.

Noel P.