Helium and phosphorus affected neat hydrocarbon (7)

'hydrocarbon' is the definition.
Both the definition and answer are singular nouns.
Perhaps they are linked in a way I don't understand?

'helium and phosphorus affected neat' is the wordplay.
'helium' becomes 'he' (chemical symbol).
'and' means one lot of letters go next to another.
'phosphorus' becomes 'P' (P is the chemical symbol for phosphorus).
'affected' is an anagram indicator.
'neat' is an anagram of 'tane'.
'he'+'p'+'tane'='HEPTANE'

Can you help me to learn more?