Unit 2: Natures Chemistry Flashcards
What do you call a compound containing only carbon to carbon single bonds?
Saturated
What happens in an addition reaction? Simple
Two molecules combine to form one
Name 3 properties of isomers (structure, series, properties)
Isomers:
- are compounds with the same molecular formula but different structural formulae
- may belong to different homologous series
- usually have different physical properties
What is volatility?
Ease of evaporation
What are 4 ways that you can predict the solubility, boiling point and volatility of a compound?
1 - the presence of O-H or N-H bonds, which implies hydrogen bonding
2 - the spatial arrangement of polar covalent bonds which could result in a molecule possessing a permanent dipole
3 - molecular size which would affect LDFs
4 - the polarities of solute and solvent. Polar or ionic compounds tend to be soluble in polar solvents, non polar compounds tend to be soluble in non-polar solvents
How else can you explain solubility, boiling point and volatility!
Type and strength of intermolecular forces present
What is an alcohol?
A molecule containing a hydroxyl functional group, -OH group
What three ways can alcohols be classified?
Primary, secondary and tertiary
What do you call an alcohol containing 2/3 hydroxyl groups?
2 - diols
3 - triols
What do hydroxyl groups do? (Polarity/bonding)
Make alcohols polar, this gives rise to hydrogen bonding
What is a carboxylic acid?
A molecule containing the carboxylic functional group, -COOH
Carboxylic acids can react with bases:
A metal oxide + a carboxylic acid = ?
A salt + water
Carboxylic acids can react with bases:
A metal hydroxide + a carboxylic acid = ?
A salt and water
Carboxylic acids can react with bases:
A metal carbonate + a carboxylic acid = ?
A salt + water + carbon dioxide
What is an ester?
A molecule containing an ester link, -COO-
Esters can be named given the: 2 reasons
1 - the name of their parent alcohol and carboxylic acid
2 - structural formulae of esters formed from primary, straight chain alcohols containing no more than eight carbons and straight-chain carboxylic acids containing no more than eight carbons
What are esters used for?
Flavourings, fragrances (pleasant fruity smell), solvents for non polar compounds that don’t dissolve in water
Molecular formulae can be befitted and structural formulae drawn for esters given the: (2 things)
1 - systematic names of esters formed from primary, straight-chain alcohols containing no more than eight carbons and straight-chain carboxylic acids containing no more then eight carbons
2 - structural formulae of their patent alcohol and carboxylic acid
How are esters formed?
A condensation reaction between an alcohol and a carboxylic acid
What happens in a condensation reaction?
Two molecules are joined together with the elimination of a small molecule
What happens when an ester link is formed?
By the reaction between a hydroxyl group and a carboxyl group, the small molecule eliminated is water
What happens when esters are hydrolysed?
It produces an alcohol and a carboxylic acid
What happens in a hydrolysis reaction?
A molecule reacts with water to break down into smaller molecules
The products of the hydrolysis of an ester can be named given the: (2 things)
1 - name of the ester
2 - structural formula of an ester formed from a straight-chain or branched alcohol and a straight-chain or branched carboxylic acid, each containing no more than eight carbons in their longest chain
How are edible fats and edible oils formed?
From the condensation of glycerol and three carboxylic acid molecules
What are carboxylic acids known as?
Fatty acids
Which has a higher melting point? Edible oils or edible fats
Edible fats
What do double bonds in fatty acid chains do?
Prevent oil molecules from packing closely together, so the greater the number of double bonds present, the weaker the van der waals forces of attraction. The greater the degree of unsaturation, the lowers the melting point
What does having a greater degree of unsaturation mean?(bp)
The lower the boiling point
What are fats and oils? 2 things
1 - a concentrated source of energy
2 - essential for the transport and storage of fat-soluble vitamins in the body
What are soaps produced by?
The alkaline hydrolysis of edible fats and edible oils
What does hydrolysis produce?
Three fatty acid molecules and one glycerol molecule
What neutralises fatty acid molecules? What does it form?
The fatty acid molecules are neutralised by the alkali, forming water-soluble, ionic salts called soaps
What can soap be used to remove?
Non-polar substances such as oil and grease
