Paper 2: Organic and Physical Chemistry

Name CH₃CH(CH₃)CH₂CH₂OH and CH₃CH₂C(O)CH₃.

Draw (describe) the two structural isomers of C₄H₁₀ and state the type of isomerism.

Describe the mechanism for the reaction of methane with chlorine in UV light to form chloromethane.

Write equations for two reactions in a catalytic converter.

Describe the mechanism for the reaction of bromoethane with aqueous sodium hydroxide.

Explain why iodoalkanes react faster than chloroalkanes in substitution reactions.

Explain how chlorine radicals from CFCs break down ozone. Include equations.

Propene reacts with hydrogen bromide. Explain which product is formed in greater amount.

Describe a test to show that a compound contains a C=C bond.

Describe how propan-1-ol can be oxidised to propanal and to propanoic acid.

Give the reagent and product when propan-2-ol is dehydrated.

Give two conditions for producing ethanol by fermentation.

An infrared spectrum shows a very broad absorption at 2500–3000 cm⁻¹ and a strong absorption at 1710 cm⁻¹. Identify the functional group and explain.

Propane and carbon dioxide both have Mr = 44. Explain how high-resolution mass spectrometry distinguishes them. (Precise masses: C 12.0000, H 1.0078, O 15.9949)

Identify the chiral centre in 2-hydroxypropanoic acid and explain what is meant by a chiral centre.

Ethanal reacts with KCN followed by dilute acid. Explain why the product is a racemic mixture.

Describe a test to distinguish an aldehyde from a ketone.

Write an equation for the formation of methyl ethanoate from ethanoic acid and methanol, and give the conditions.

Describe the mechanism for the reaction of ethanoyl chloride with ammonia.

Explain why ethanoic anhydride rather than ethanoyl chloride is used to make aspirin industrially.

The enthalpy of hydrogenation of cyclohexene is −120 kJ mol⁻¹. Benzene's is −208 kJ mol⁻¹. Explain what this shows about benzene's structure.

Describe how the nitronium ion is formed and outline the mechanism for the nitration of benzene.

Place ammonia, ethylamine and phenylamine in order of base strength (strongest first) and explain.

Give a reagent for converting propanenitrile into propylamine and state the type of reaction.

Draw (describe) the repeating unit of the polyester formed from ethane-1,2-diol and benzene-1,4-dicarboxylic acid.

Explain why polyesters are biodegradable but poly(alkenes) are not.

Explain what is meant by a zwitterion, using aminoethanoic acid as an example.

Explain how cisplatin acts as an anticancer drug.

Explain the role of hydrogen bonds in the secondary structure of proteins.

Describe a two-stage synthesis of ethylamine from ethene. Give reagents, conditions and equations.

Predict the ¹H NMR spectrum of ethyl ethanoate, CH₃COOCH₂CH₃: number of peaks, integration ratio and splitting.

Explain why TMS and CDCl₃ are used in NMR spectroscopy.

In thin-layer chromatography, a spot moved 2.4 cm and the solvent front 6.0 cm. Calculate the Rf value.

Explain how gas chromatography separates the components of a mixture.

Explain why a small increase in temperature causes a large increase in reaction rate.

Burning 0.460 g of ethanol (Mr 46.0) heated 100 g of water by 25.0 K. Calculate the enthalpy of combustion of ethanol in kJ mol⁻¹. (c = 4.18 J g⁻¹ K⁻¹)

Explain why this value is much less exothermic than the data-book value of −1367 kJ mol⁻¹. Give three reasons.

Calculate the volume, in cm³, occupied by 0.0100 mol of CO₂ at 100 kPa and 298 K.

Describe chemical tests that would allow you to distinguish between propanal, propanone, propan-1-ol and propanoic acid. Give reagents and observations.