Question

Butene has two isomers—one with methyl groups on the same side of the double bond and the other with methyl groups on the opposite side. What kind of isomers are these?

Answer 1

Try this: http://en.wikipedia.org/wiki/Cis%E2%80%93trans_isomerism

Answer 2

Check this n reply if you have any query!

Answer 3

I think they are asking the type of isomers they are and since it's been 11 hours, shall we discuss the answer? I think it's cis and trans isomers.