[elefantsnablar]

Hi!

I've been given the alkene "3-ethyl-4-propylheptane". I found nothing wrong in the name, however, the 4-prefix (before propyl) is unnecessary since if the propyl would be sitting on ANY other carbon, the longest carbon chain would change and it would no longer be a heptane.

My question is, is "3-ethylpropylheptane" a legit name, or must I number all branches if I've numbered one?

Grateful for all responses, thanks!

[discodermolide]

I'm afraid you need to put the number in.
Just to note your compound is not an alkene but an alkane.

[elefantsnablar]

Allright, I'll state the final name as "3-ethyl-4-propylheptane" then. Thank you very much for your input!