We are inundated with persuasive messages from marketers, politicians, and others. But what does the evidence actually say?

You can work out the molecular formula from the empirical formula, if you know the relative mass formula (M r) of the compound. Add up the atomic masses of the atoms in the empirical formula.

In contrast, empirical models aim to verify the qualitative predictions of theoretical models and convert these predictions to precise, numerical outcomes. For example, a theoretical model of an agent ...