Final answer:
The empirical formula represents the lowest whole-number mole ratio of the elements in a compound. To determine it, convert element masses to moles, divide by the smallest mole value, and express as the simplest ratio. It differs from the molecular formula, which shows exact atom counts.
Step-by-step explanation:
The simplest whole number ratio of moles of each element in a compound is known as the empirical formula. The empirical formula represents the relative number of atoms of each element in the simplest ratio. Unlike the molecular formula, which shows the actual number of atoms in a molecule, the empirical formula may not provide information about the actual number of atoms but gives the simplest ratio of elements.
To determine an empirical formula, you start by measuring the mass of each element in a compound. You then convert these masses to moles using the molar mass of each element. The moles of each element are then divided by the smallest number of moles obtained, leading to a whole-number ratio. This ratio is used to write the empirical formula. For instance, the molecular formula for glucose, C6H12O6, simplifies to the empirical formula CH2O, reflecting the lowest whole-number ratio of carbon, hydrogen, and oxygen in the compound.