17. Carbonyl compounds
A section of Chemistry, 9701
Listing 10 of 304 questions
Oxygen-containing organic compounds may contain a number of different functional groups including alcohol, aldehyde, carboxylic acid, ester or ketone functional groups. These functional groups may be identifi ed by their reactions with specifi c reagents. On treating compounds containing each of these functional groups with the reagents below, only fi ve reactions occur. Complete the table by placing a tick () in each box where you believe a reaction will occur. You should place no more than fi ve ticks in the table. reagent alcohol R2CHOH aldehyde RCHO carboxylic acid RCO2H ester RCO2R' ketone RCOR’ NaHCO3 Na Cr2O7 2– / H+ Compound G has the empirical formula CH2O and Mr of 90. An aqueous solution of G is neutral. There is no reaction when G is treated with NaHCO3. When 0.30 g of pure G is reacted with an excess of Na, 80 cm3 of H2, measured at room temperature and pressure, is produced. What functional group do these two reactions show to be present in G? Use the data to calculate the amount, in moles, of hydrogen atoms produced from 0.30 g of G. Hence, show that each molecule of G contains two of the functional groups you have given in . Treatment of G with 2,4-dinitrophenylhydrazine reagent produces an orange solid. When G is warmed with Fehling’s reagent, no reaction occurs. What functional group do these reactions show to be present in G? Draw the displayed formula of this functional group. Use your answers to and to deduce the structural formula of G. Compound G can be both oxidised and reduced. When G is heated under refl ux with acidifi ed K2Cr2O7, compound H is formed. Give the structural formula of compound H. When G is reacted with NaBH4 under suitable conditions, compound J is formed. Give the structural formula of compound J.
9701_s12_qp_22
THEORY
2012
Paper 2, Variant 2
View
Modern methods of analysis have had far-reaching effects on a number of branches of science including medicine, forensic science, environmental monitoring and archaeology. Outline, in simple terms, the technique of DNA fi ngerprinting. Complete the table by indicating whether the items can be used for DNA fi ngerprinting. Use a tick ( ) for items which can be used for DNA fi ngerprinting and a cross for items which cannot. item for testing suitable for DNA fi ngerprinting human hair piece of a fl int tool piece of Iron Age pot piece of Roman leather Various forms of chromatography can be used to separate and analyse mixtures. HPLC (high performance liquid chromatography) can be used to separate each of the following mixtures. State another method of chromatography which would separate each mixture. insecticides in a sample of water dyes present in a foodstuff drug residue in an athlete’s urine 
9701_s13_qp_41
THEORY
2013
Paper 4, Variant 1
View
Modern methods of analysis have had far-reaching effects on a number of branches of science including medicine, forensic science, environmental monitoring and archaeology. Outline, in simple terms, the technique of DNA fi ngerprinting. Complete the table by indicating whether the items can be used for DNA fi ngerprinting. Use a tick ( ) for items which can be used for DNA fi ngerprinting and a cross for items which cannot. item for testing suitable for DNA fi ngerprinting human hair piece of a fl int tool piece of Iron Age pot piece of Roman leather Various forms of chromatography can be used to separate and analyse mixtures. HPLC (high performance liquid chromatography) can be used to separate each of the following mixtures. State another method of chromatography which would separate each mixture. insecticides in a sample of water dyes present in a foodstuff drug residue in an athlete’s urine 
9701_s13_qp_43
THEORY
2013
Paper 4, Variant 3
View
Questions Discovered
304