Isomerism: Structural Isomerism & Stereoisomerism (CIE AS Chemistry)

Evening primrose oil has been shown to reduce high blood pressure and improve heart health. The oil is made from seeds, within which the active compound gamma-linolenic acid is found. 

How many stereoisomers does gamma-linolenic acid have?

How many structural isomers are there of tribromopropane, C₃H₅Br₃?

How many isomeric esters have the molecular formula C₅H₁₀O₂?

11-cis retinal, C₂₀H₂₈O, is found in the retina of animal eyes and is required for vision. 

An 11-cis retinal molecule contains the following functional groups:

• 1 x aldehyde group
• 1 x cyclohexene ring
• 1 x aliphatic side chain

Within the side chain, there is a double bond between carbons 11 and 12.

Which letter is associated with the correct pair? 

	Arrangement of atoms around the adjacent carbons 11 and 12	Total number of carbon-carbon double bonds
A		5
B		6
C		5
D		6

Which of the following compounds is both chiral and acidic?

Cholesterol is an important biological molecule produced by the liver. It is used in the production of steroid hormones and vitamin D. 

How many chiral centres are there in one molecule of cholesterol? 

Including structural and stereoisomers, how many isomeric products are produced when alcoholic NaOH reacts with 2-bromobutane?

How many isomers, including structural and stereoisomers, with the formula C₅H₁₀ have structures that involve π bonding?