What is the simplest whole-number ratio of atoms in a molecule or formula unit called?

Count the number of each type of atom in the equation below, and then balance the equation. write in the numbers of atoms and coefficients. add a 1 if there should be no coefficient. cs2(l) + o2(g) → co2(g) + so2(g) c [ ] s [ ] o > c [ ] s [ ] o [ ] cs2(l) + [ ] o2(g) > [ ] co2(g) + [ ] so2(g)