Esters, fats and oils Flashcards
How are esters made?
By a condensation reaction between an alcohol and a carboxylic acid, that are joined together through the elimination of water.
What is the ester link?
COO
What are condensation reaction?
Reactions that involve the elimination of small molecules in order to combine two molecules to form a larger molecule.
How do you name an ester?
(Alcohol)yl (Acid)oate - The OH from the carboxylic acid is removed and the H from the alcohol is also removed.
What are the properties of esters?
They have a pleasant fruity smell and are non-polar, hence do not dissolve in water or alcohols.
What are some uses of esters?
They can be used as solvents for paints and other non-polar compounds and can dissolve coloured compounds like nail polish. They can also be used as flavourings and in scented products.
How are esters broken down?
Esters are broken down through hydrolysis, which is when an ester reacts with water to form an alcohol and a carboxylic acid.
What are edible fats and oils?
A special type of ester called a tri-ester (as they contain 3 ester links) found in a variety of foods.
How are edible fats and oils formed?
They are formed from the condensation of propan-1,2,3-triol and 3 fatty acid molecules.
How are fats formed?
Fats are formed from saturated fatty acids.
How are oils formed?
Oils are formed from unsaturated fatty acids.
Why are oils liquid at room temperature?
Oils are liquid at room temperature because the fatty acids are unsaturated. The double bonds cause an uneven, distorted structure, making it difficult for molecules to pack closely together.
Why are fats solid at room temperature?
Fats are solid at room temperature because the fatty acids are saturated, allowing for the efficient packing of fat molecules, meaning that the intermolecular forces of attraction can hold the fat molecules together.
How can you determine the degree of unsaturation in an oil?
The bromine molecules add across the carbon–carbon double bonds in an addition reaction. The greater the number of double bonds present in a substance, the more bromine solution can be decolourised.
Explain, briefly, the importance of fats and oils in the diet.
They are an essential part of our diet due to their non-polar structure, which allows them to dissolve and transport a number of essential vitamins (like A and D).
