Isomerism 09B

Question 1

difference between cis and trans isomers

Answer 1

cis isomers: same group on the same end bonded to each of the carbon atoms in the C=C carbon bond

trans isomers: same group on opposite ends that are bonded to each C atom in the C=C double bond

Question 2

what allows an isomer to be cis or trans?

Answer 2

when they have a:

1. RESTRICTED ROTATION about the C=C double bond or in a ring of 7 or more carbon atoms in its main chain.
2. TWO PAIRS of the TWO OR MORE GROUPS, where one of each pair is attached to one of the carbon atoms in the C=C carbon bond, as long as the groups attached to each carbon atom of the double bond are able to switch positions through rotation. two groups cannot be bonded to the same carbon atom in the double bond.

Question 3

formula for the number of stereoisomers

Answer 3

2^m, where m is the number of double binds that can result in cis-trans isomers