[Charkol]

I have this question that I do not understand.

"How many carbon atoms does an alkane (not a cycloalkane) need before it is capable of existing in enantiomeric forms?"

The answer to this question is in the solutions manual.  The answer is 7 carbon atoms.

I thought even a methane molecule could be enantiomeric.  For instance clorofluorobromomethane.

What am I missing in this question?

[karlosshughes]

The question says alkane, which implies that only carbon and hydrogen atoms are present. While bromochlorofluoromethane is chiral and can exist in two enantiomers, an alkane containing only carbon and hydrogen would need seven carbons:
                                                     Et               
                                                     |                   
                                              Me - c -H
                                                     |
                                                     Pr           
Me = 1 carbon, Et = 2 carbons, Pr = 3 carbons. Therefore, the minimum number of carbons needed is 7.

(For a clearer structure, just Google 3-methyl hexane.     

[Charkol]

I see.  Yes, I must have generalized the term alkane into any single bonded carbon chain.  This makes sense.  Thanks much.