[Kaizer]

C2HClBrF

Draw as many Lewis structures for C2HClBrF as you can. How many isomer possibilities are there? You will encounter a problem assigning cis and trans designations to these isomers. What is that problem? Can you invent a way of naming these isomers that gets around this short-coming of the cis and trans way of naming double bond isomers? Describe this method.

^This chem question is killing me. I'd much appreciate it if someone could help me out. Thanks!

[Fluorine]

First you should draw out the molecule or it's skeleton to get an idea of what you're dealing with. From the formula HC₂BrClF we can determine it's an ethene with three halogen substitutions. It can't be named using cis/trans system without ambiguity so you'll have to use E/Z naming system. These follow CIP priority for naming E or Z.

Try naming these two with E/Z notation.