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Flashcards in How Do you make a... Deck (13)
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1
Q

Carboxylic acid

A

Oxidation of primary alcohol

  • heat an alcohol under reflux with potassium/sodium dichromate and sulphuric acid
  • it will not undergo anymore reaction
2
Q

Ester

A

Esterification

- react an alcohol with a carboxylic acid in the presence of an acid catalyst

3
Q

Aldehyde

A

Oxidation of primary alcohol

  • heat an alcohol with potassium/sodium dichromate and sulphuric acid
  • distil immediately to prevent any further reaction
4
Q

Ketone

A

Oxidation of an secondary alcohol

  • heat an alcohol with potassium/sodium dichromate and sulphuric acid to make a ketone
  • it will not undergo anymore reaction
5
Q

How do you make Alkenes from alkanes

A

Cracking

6
Q

How do you make alkanes from alkenes

A

Hydrogenation

- 150 degrees, nickel catalyst in a reaction chamber

7
Q

How to make Haloalkanes from alkanes

A

Radical substitution

  • UV light
  • Draw radical substitution to form chloromethane
8
Q

How to make Haloalkanes from alkenes

A

Halogenation

  • add a halogen across a C=C bond the alkene becomes saturated and a dihaloakane is produced, this can be used to test for saturation
  • when bromine or iodine is added there is no reaction
9
Q

polymers from alkenes

A

Addition polymerisation
- during polymerisation monomers have there pie bond broken and the electrons from each pie bond make and sigma bond with a neighbouring carbon atom

10
Q

How do you make alcohol from alkenes

A

Hydration

  • gaseous alkene and steam
  • phosphoric acid catalyst at 300 degrees and 65 atm
11
Q

How do you make alkenes from alcohols

A

Dehydration

  • alcohol heated with a strong acid (sulphuric acid) at 170 degrees under reflux
  • water is eliminated to make an alkene, the OH group from one carbon atom and H group from another carbon atom are lost to form a water molecule, the pie bond forms between 2 adjacent carbon atoms
12
Q

How do you make alcohols from haloalkane

A

Hydrolysis using aqueous alkali
- haloalkane is heated under reflux with an aqueous solution containing hydroxide ions an alcohol is made

Nucleophilic substitution reaction

  • water is the reactant that provides the hydroxide ions that act as nucleophiles - if water is used one of the H-O bonds in a molecule undergoes hetrolytic fission to product the nucleophile OH-
  • this species attacks the electron deficient carbon atom in the haloalkane molecules then once the nucleophile has bonded to the haloalkane, the C-X bond undergoes hetrolytic fission to produce a halide ion
13
Q

How do you make haloalkanes from alcohols

A

Halide Substitution

  • Hydrogen halide is the reagent that would be used but the Halide would be the species directly involved in the reaction
  • sulphuric acid or a strong acid catalyst is used and the mixture is heated to increased the rate of reaction
  • However when iodide is reacted phosphoric acid is used because the sulphuric acid oxidises iodide ions to iodine so the yield of iodoalkane is low