AC7: Isomerism

Question 1

What are the 2 key points to structural isomerism

Answer 1

same molecular formula
different structural formula

Question 2

What are the 2 key points to steroisomerism

Answer 2

same structural formula
different arrangement of atoms in space

Question 3

What are optical isomers

Answer 3

non-superimposable mirror images, they have a chiral centre

Question 4

what is a chiral centre

Answer 4

an atom bonded to 4 different types of groups

Question 5

how do you denote a chiral centre

Answer 5

with an asterisk

Question 6

how can you work out the number of stereoisomers from how many chiral centres there are

Answer 6

2^n where n is the number of chiral centres as long as all chiral centres are different, is the number of stereoisomers there are

Question 7

How do optical isomers react towards non-chiral and chiral reagents

Answer 7

optical isomers have identical physical & chemical properties towards non-chiral reagents and materials, but react differently with chiral reactants

Question 8

how do you know if an optical isomer is denoted with a R prefix or a S prefix

Answer 8

atoms going 1-4 in clockwise = R
atoms going 1-4 in anticlockwise = S