What are the priorities for substituent groups on a cyclohexane? I was wondering about this specific scenario:
If you have a cyclohexane, for example, and the cyclohexane has two consecutive substituent groups, for example a methyl group and an ethyl group, how do you decide where the numbering starts?
Would it be 1-ethyl-2-methylcyclohexane or would it be 2-ethyl-1-methylcyclohexane?
Whoever answers this, could you just give some sort of general rules on what to do in this situation (e.g. does it follow alphabetical order, etc.)?
If the numerical sequence of locants is equivalent, the numbering should be assigned to correspond with alphabetical order. Hence, in your example, correct would be 1-ethyl-2-methylcyclohexane. Quoting the IUPAC Blue Book, Rule A-2.4:


  If two or more side chains are in equivalent positions, the one to be assigned the lower number is that cited first in the name.