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9 Cards in this Set
- Front
- Back
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What does volatility mean? |
Tendency for a molecule to evaporate at normal temperatures |
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What are the two physical properties of alcohols? |
•low volatility because the hydrogen bonds between the -OH group require a lot of energy to overcome, same reason for high boiling point •soluble in water because the -OH group can form hydrogen bonds with water molecules. Solubility decreases as chain length increases because the influence of the -oh group decreases |
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Describe primary secondary and tertiary alcohols |
Primary- oh group is attached to carbon atom with two hydrogens and one alkyl group Secondary- oh group is attached to carbon with one hydrogen and two alkyl groups Tertiary- oh group is attached to carbon with no hydrogens and three alkyl groups |
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What is the usual oxidising agent used to oxidise alcohols? |
Solution of k2cr2o7 acidified with h2so4 |
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What is the colour change seen when alcohols are oxidised? |
Orange to green |
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Explain the oxidation of primary alcohols |
Primary alcohols can be oxidised to aldehydes or carboxylate acids Aldehydes- •gentle heating •distilled out to prevent further oxidation to carboxylic acid Carboxylic acid: •heated strongly under reflux with excess to make sure all of alcohol is oxidised |
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Explain oxidation of secondary alcohols |
Makes ketones, can’t be oxidised further •heated under reflux |
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Why can’t tertiary alcohols be oxidised? |
No hydrogen atoms on the carbon where oh group is attached |
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What is dehydration of alcohols? |
-elimination of water -heated under reflux with acid catalyst -example of an elimination reaction |
