Compound B is a liquid with a fruity smell. [Structure of B: an ethyl ester of bromoethanoic acid, CH₃CHBrCOOCH₂CH₃] The reaction scheme shows how B can be made from ethanol, C₂H₅OH. [Reaction Scheme: C₂H₅OH (reacion 1, [O]) -> HOCH₂COOH (reaction 2) -> CH₂BrCOOH (reaction 3, C₂H₅OH and H₂SO₄) -> B (ethyl ester of bromoethanoic acid, CH₃CHBrCOOCH₂CH₃)]

1. (a)(i)Reaction 1 is an oxidation reaction. Give the reagent(s) and conditions required for reaction 1. reagent(s) ...................................................................................................................................................... conditions ......................................................................................................................................................[2]
2. (a)(ii)Construct an equation to represent reaction 1. Use [O] to represent an oxygen atom from the oxidising agent in this reaction.[1]
3. (a)(iii)Suggest the type of reaction that occurs in reaction 2.[1]
4. (a)(iv)H₂SO₄ acts as a homogeneous catalyst in reaction 3. Explain why H₂SO₄ is described as homogeneous.[1]
5. (b)Reaction 2 needs to take place in the absence of water to prevent formation of compound C. [Structure of C: HOOC-COOH (ethanedioic acid)] If C is present in the reaction mixture of reaction 3, a different compound, compound D, will also form. Compound D has two identical functional groups. The infrared spectrum of D shows strong absorptions at 1100 cm⁻¹ and 1720 cm⁻¹, but no absorption due to O-H bonds. Use the Data Booklet to identify the functional group present in D. Explain your answer as fully as you can.[3]
6. (c)(i)Some other reactions of C are shown. [Reaction scheme: C (HOOC-COOH) reacts with Na₂CO₃ to form E. C (HOOC-COOH) reacts with F ((CH₂OH)₂) via SOCl₂ to form G ((CH₂Cl)₂)] Draw the structure of E.[1]
7. (c)(ii)Suggest why NaBH₄ is not a suitable reagent to make F, (CH₂OH)₂, from C. Explain your answer.[1]
8. (c)(iii)Construct an equation for the reaction of (CH₂OH)₂ with SOCl₂ to form G, (CH₂Cl)₂.[1]
9. (d)Explain why C is very soluble in water.[1]

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