Most of them seem fine. Should 4 not be 3,3-dimethylhexane? I would also tend to expand 6 (i.e. draw out all the bonds), as I've often heard that it can be misinterpreted with the bonds going to hydrogen, rather than the carbon, but I'm not sure if that's necessary. [i]Edit: again, I'm not sure how pedantic this is (or even wrong?) but for 1, I'm not sure you'd usually have the "-" before hexane, they're normally used between numbers and the groups, aren't they?[/i] [i]Edit 2: I know the solution isn't always available, particularly for more complex molecules, but can I suggest a site like wolframalpha to check some solutions. Assuming the molecule is recognised (I find it's around 50/50) you'll be able to see the full structure of the molecule you've named.[/i]