ocr A Level Chemistry A H432-02 Question Paper.

ocr A Level Chemistry A H432/02 Question Paper
June2023 Verified.
Acyl chloride (R-COCl) → Carboxylic acid (R-COOH) - ansH₂O
Room temperature

Hydrolysis

Acyl chloride (R-COCl) → Pimary amide (R-C(O)NH₂) - ansNH₃ (ammonia)

Acyl chloride (R-COCl) → Secondary amide (R-C(O)NH-R') - ansPrimary amine (R-NH₂)

Alcohol (R-CH₂OH) → Ester (R'-COO-R) - ansCarboxylic acid (R'-COOH)/ concentrated H₂SO₄ catalyst
Byproduct: H₂O
OR
Acyl chloride (R'-COCl) (no catalyst)
Byproduct: HCl
OR
Acid anhydride ((R'-COO)₂O)or(R'-COOCO-R') (no catalyst)
Byproduct: Carboxylic acid (R'-COOH)

Esterification

Alcohol (R-OH) → Alkene - ansConcentrated H₂SO₄ or H₃PO₄ (phosphoric acid)
Heat

Elimination of water/ Dehydration

Alcohol (R-OH) → Haloalkane (R-X) - ansSodium halide (NaX) / conc. H₂SO₄ (this forms HX in situ)
Heat under reflux

Aldehyde (R-CHO) → Hydroxynitrile (R-CH(OH)(C≡N))
Ketone (R-CO-R') → Hydroxynitrile
(R-C(OH)(C≡N)-R') - ansNaCN (sodium cyanide)/ H⁺ (forms HCN in situ)

Nucleophilic addition

Aldehyde (R-CHO) → Primary alcohol (R-CH₂OH)
Ketone (R-CO-R') → Secondary alcohol (R-CH(OH)-R') - ansNaBH₄ / H₂O (aqueous sodium
tetrahydridoborate)

Reduction
Two molecules of reducing agent ([H]) are used in the reaction

Alkane → Haloalkane (R-X) - ansHalogen (X₂)
Ultraviolet light (UV)

Free radical substitution

Alkene → Alcohol (R-OH) - ansH₂O (steam) / H₃PO₄ (phosphoric acid)

Hydration

Alkene → Alkane - ansH₂
Ni catalyst
150⁰C