It's a bit more complicated than that: In he structure, the two oxygen atoms are single bonded to each other and are bonded to one cesium atom each. The oxygen-oxygen bond is covalent (electrons shard), but the oxygen-cesium bond is ionic (electrons transferred from cesium to oxygen). This would be classified as ionic, but it's not exactly that.
This means for every number of Carbon (C) atoms, there are twice as many Hydrogen (H) atoms with an additional two added onto that.
Therefore, if there is one Carbon Atom, and we multiply that by two, and then add an additional two, we get 4 Hydrogen atoms, so CH4, which is our first Formulae
Secondly, if we have eight Carbon Atoms, and we multiple that by two (16), and then add an additional two, we get 18 Hydrogen atoms, so C8H18, which is our second Formulae
The other Formulas do not follow this 'General Formula'
