CIE Nov 2014 v3 Paper 4 Q7

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14 Section B Answer all the questions in the spaces provided. (a) Explain what is meant by the term partition coef cient. PMT[2] (b) When 20 cm3 of ethoxyethane were shaken with 75 cm3 of an aqueous solution containing 5.00 g of an organic compound, J, in 75 cm3 of water, it was found that 2.14 g of J were extracted into the ethoxyethane. Calculate the partition coef cient, Kpartition, of J between ethoxyethane and water. Kpartition =[2] (c) In a new experiment 10 cm3 of ethoxyethane were shaken with 75 cm3 of an aqueous solution containing 5.00 g of J and the layers were separated. The aqueous layer was shaken with a second 10 cm3 portion of ethoxyethane and the layers were separated. The two organic layers were combined. Use the value of Kpartition you calculated in (b) to calculate the total mass of J extracted by this procedure. total mass of J =[2] (d) Paper chromatography and gas / liquid chromatography both rely on the partition of compounds between mobile and stationary phases. (i) Identify the mobile phase in paper chromatography.(ii) Suggest what type of liquid is used for the stationary phase in gas / liquid chromatography.UCLES 2014 9701/43/O/N/14<br /> PMT (iii) Both these techniques can be used to separate mixtures. 15 State what you would measure in order to distinguish between the components in the mixture in 1. paper chromatography,2. gas / liquid chromatography.[4] (e) A mixture of three compounds was analysed by paper chromatography using a non-polar solvent. The resulting chromatogram is shown. solvent front mixture Identify which compound is responsible for each spot. spot compound CO2H CH2OH CO2H CO2HUCLES 2014 9701/43/O/N/14 [1] [Total: 11] [Turn over<br />

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