The temperature of water is cooler in deep oceans. The temperature there goes to 0°C to -3°C below which the water freezes. The water on the surface of the oceans and deep inside it varies because of the difference in energy of the two layers. One of the widest use of cold water is air conditioning. Cold water has a higher density than warm water. Water gets colder with profundity since chilly, salty sea water sinks to the base of the sea beds underneath the less dense hotter water close to the surface.
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'