9701_s09_qp_1
A paper of Chemistry, 9701
Questions:
40
Year:
2009
Paper:
1
Variant:
0
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2
A household bleach contains sodium chlorate(, NaClO, as its active ingredient. The concentration of NaClO in the bleach can be determined by reacting a known amount with aqueous hydrogen peroxide, H2O2. NaClO+ H2O2→ NaCl+ O2+ H2OWhen 25.0 cm3 of bleach is treated with an excess of aqueous H2O2, 0.0350 mol of oxygen gas is given off. What is the concentration of NaClO in the bleach?
11. Group 17  →  11.4. The reactions of chlorine
2. Atoms, molecules and stoichiometry  →  2.4. Reacting masses and volumes (of solutions and gases)
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9
When copper is extracted from its ores, the metal is not pure enough for electrical uses. The impure copper, which contains small amounts of silver and gold, is purified by electrolysis. During this process a ‘sludge’ forms beneath the anode which is found to contain silver and traces of gold. Why is silver found in this sludge?
11. Group 17  →  11.3. Some reactions of the halide ions
11. Group 17  →  11.4. The reactions of chlorine
15. Halogen compounds  →  15.1. Halogenoalkanes
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10
The diagram shows the Maxwell-Boltzmann energy distribution curve for molecules of a mixture of two gases at a given temperature. For a reaction to occur the molecules must collide together with sufficient energy. number of molecules Ea2 Ea1 energy Ea is the activation energy for the reaction between the gases. Of the two values shown...
8. Reaction kinetics  →  8.2. Effect of temperature on reaction rates and the concept of activation energy
8. Reaction kinetics  →  8.1. Rate of reaction
8. Reaction kinetics  →  8.3. Homogeneous and heterogeneous catalysts
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18
Mohr’s salt is a pale green crystalline solid which is soluble in water. It is a ‘double sulfate’ which contains two cations, one of which is Fe2+. The identity of the second cation was determined by heating solid Mohr’s salt with solid sodium hydroxide and a colourless gas was evolved. The gas readily dissolved in water giving an alkaline solution. A grey-green solid residue was also formed which was insoluble in water. What are the identities of the gas and the solid residue?
4. States of matter  →  4.2. Bonding and structure
12. Nitrogen and sulfur  →  12.1. Nitrogen and sulfur
9. The Periodic Table: chemical periodicity  →  9.2. Periodicity of chemical properties of the elements in Period 3
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20
The compound known as ‘gamma-linolenic acid’ is found in significant amounts in the seeds of the Evening Primrose plant. There is evidence that the compound may help patients with diabetes. CH3(CH2)4CH=CHCH2CH=CHCH2CH=CH(CH2)4CO2H gamma-linolenic acid How many cis-trans isomers does gamma-linolenic acid have?
13. An introduction to AS Level organic chemistry  →  13.1. Formulas, functional groups and the naming of organic compounds
13. An introduction to AS Level organic chemistry  →  13.4. Isomerism: structural isomerism and stereoisomerism
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28
Carvone gives the characteristic flavour to caraway and spearmint. O CH3 CH2 H3C C carvone Prolonged heating of carvone with hot concentrated acidified potassium manganate(produces carbon dioxide and a compound X. X contains nine carbon atoms and reacts with 2,4-dinitrophenylhydrazine reagent. What is the maximum number of molecules of 2,4-dinitrophenylhydrazine that will react with one molecule of X?
17. Carbonyl compounds  →  17.1. Aldehydes and ketones
18. Carboxylic acids and derivatives  →  18.1. Carboxylic acids
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