It is not that I didn't google it before asking it here, I could it find it anywhere. My question must be simple but I'm really stuck upon it. How do you name long hydrocarbon chains? Like $\ce{C21H44}$, $\ce{C30H62}$, $\ce{C100H202}$ etc.
I found this when I googled but I didn't quite understand it.
Use the table mentioned in the linked article, §NT-1.1:
1 mono- or hen-* 10 deca- 100 hecta- 1000 kilia-
2 di- or do-* 20 icosa-** 200 dicta- 2000 dilia-
3 tri- 30 triaconta- 300 tricta- 3000 trilia-
4 tetra- 40 tetraconta- 400 tetracta- 4000 tetralia-
5 penta- 50 pentaconta- 500 pentacta- 5000 pentalia-
6 hexa- 60 hexaconta- 600 hexacta- 6000 hexalia-
7 hepta- 70 heptaconta- 700 heptacta- 7000 heptalia-
8 octa- 80 octaconta- 800 octacta- 8000 octalia-
9 nona- 90 nonaconta- 900 nonacta- 9000 nonalia-
just enumerate the digits of the carbon and add "-ne".
So $\ce{C21H44}$ becomes "hen-" "icosa-" "ne" = henicosane / heneicosane (the latter is just a spelling variation).
There are exceptions like propane ($\ce{C3H8}$) but these only occur for small molecules, up to $\ce{C4H10}$.
