What do the COEFFICIENTS in a chemical reaction represent?

The sum of the atoms or ions in the compound

The mole ratio of atoms or ions in the compound

The sum of the species in a chemical reaction

The mole ratio of species in a chemical reaction

What is a main difference between a mixture and a pure substance? a mixture is only a liquid, but a pure substance can be in any state.a mixture looks the same throughout, but a pure substance does not.1 a mixture can vary in composition, but a pure substance has a set composlo a mixture can be made up of a single compound, but a pure substance car