St Elizabeth Ss Nkoowe Senior Five Chemistry End Of Year 2025

pg. 1 ST ELIZABETH SS NKOOWE S5 CHEMISTRY PAPER 1 END OF YEAR 2025 DURATION: 2 HOURS: 45 MINUTES INSTRUCTIONS: ATTEMPT ALL Item 1 In a chemical industry a manager wishes to obtain an unsaturated compound from compound T. when the industrial chemist burnt 7.5g of T which the container label is composed of carbon, hydrogen and rest being oxygen, this organic compound T produced 17.8g of carbondioxide and 9.27g of water. In another experiment when 0.225g of T was vapourized at 127oC and 760mmHg it occupied 100cm3. The chemist continued to dehydrate one of the isomers of T using concentrated sulphuric acid and produced compound X which on ozonolysis gave propanone and methanal. The manager is seeks to find out the molecular formula of T, nomenclature of possible isomers of T and its derivatives and also how conversions can be effected in obtaining derivatives of T. Task As a chemistry student, help the industrial chemist (a) (i) Determine the molecular formula of T for use in the laboratory ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ pg. 2 ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ____________________________________________________________________________ (4 scores) (b) (i) By writing all possible isomers of T and IUPAC name, Identify the isomer to be used to produce compound X ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ _____________________________________________________________________________ (3 scores) (ii) Identify the required hydrocarbon X and write all its possible isomers and respective IUPAC names ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ _____________________________________________________________________________ ( 2 scores) (b) write the equations for the conversions of; (i) isomer of T identified to X and suggest mechanism ______________________________________________________________________________ ______________________________________________________________________________ pg. 3 ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ _____________________________________________________________________________ (3 scores) (ii) X to propanone and methanol ______________________________________________________________________________ …