National 5 Chemistry in Society Test 1

Transcription

1 National 5 hemistry in Society Test Name 30. Which two substances are required for corrosion of iron to occur? 2. Nitrogen and carbon dioxide Nitrogen and oxygen Water and carbon dioxide Water and oxygen 4. The ion-electron equation for the oxidation and reduction steps in the reaction between magnesium and silver(i) ions are: Mg --> Mg e g + +e --> g The overall redox equation is Mg + 2g + --> Mg g Mg + g+ --> Mg 2+ + g Mg + g + +e --> Mg 2+ + g + 2e Mg + 2g --> Mg g + Which ion gives a blue colour with ferroxyl indicator? O H - (aq) Fe 2+ (aq) Fe 3+ (aq) u 2+ (aq) 3. Some metals can be obtained from their oxides by heat alone. Which of the following oxides would produce a metal when heated? alcium oxide opper oxide Zinc oxide Silver oxide 5. The ion-electron equation Ti(s) -->Ti 2+ (aq) + 2e represents the reduction of titanium atoms reduction of titanium ions oxidation of titanium atoms oxidation of titanium ions. 6. iopol is a polymer which is natural and biodegadeable synthetic and biodegadeable natural and non-biodegadeable synthetic and non-biodegadeable

2 7. Which poisonous gas is always made when polymers burn? 2. Which of the following could be made by precipitation arbon monoxide hlorine arbon dioxide yanide Silvernitrate Silverchloride Sodium nitrate Sodium chloride 8. Which of the following pairs of metals would givethelargestvoltageifusedina electrochemical cell? 3. water sample gives a yellow flame colour, which element is present in the water? opper and tin Tinandiron Iron and zinc Zinc and copper hlorine Iron Sodium Potassium 9. Which element is not an essential component of fertilisers? arbon Nitrogen Potassium Phosphorus 0. What fraction of a radioactive substance wil remainafter3halflives? /2 /4 /6 /8. Polypropene softens when it is heated, this indicatesthatitis biodegradeable thermosetting synthetic thermoplastic 4. n atom of Uranium emits an alpha particle, which element is formed in this change? Thorium Protactinium Neptunium Plutonium 5. Galvanising involves covering iron with which metal? opper Tin Magnesium Zinc 5 National 5 hemistry

3 6. Titanium is an important metal. (a) Titanium can be extracted from titanium dioxide. The titanium dioxide is reacted with carbon and chlorine to produce impure titanium chloride and carbon dioxide. The impure titanium chloride is purified by distillation. Magnesium metal is added to the pure titanium chloride producing titanium and magnesium chloride. omplete the flow chart to show the extraction process. 2 mixture of titanium and nickel is used to make the alloy, Nitinol. The composition of Nitinol is shown in the table. alulate the mass of titanium in 20g of nitinol. (3) National 5 hemistry

4 7. mmonia is made when nitrogen and hydrogen react together. The table below shows the percentage yields obtained when nitrogen and hydrogen react at different pressures. (a) raw a line graph of percentage yield against pressure. Use appropriate scales to fill most of the graph paper. 2 (c) Use your graph to estimate the percentage yield of ammonia at 50 atmospheres....% Name the catalyst used to make ammonia. (4) National 5 hemistry

5 8. The table contains information on minerals. Mineral cinnibar Formula HgS fluorite af 2 gibbsite l(oh) 3 haematite Fe 2 O 3 zinc blende ZnS (a) alculate the percentage by mass of calcium in fluorite, af 2. Iron metal can be extracted from haematite, Fe 2 O 3 by heating with carbon monoxide, carbon dioxide is produced in this reaction. Write an equation using symbols and formulae,forthisreaction. There is no need to balance the equation. (c) Name a metal which has to be extracted by electrolysis of the molten ore. (3) National 5 hemistry

6 9. The element iodine has only one isotope that is stable. Several of the radioactive isotopes of iodine have medical uses. Iodine-3, for example, is used in the study of the thyroid gland and it decays by beta emission. (a) omplete the following equation for beta decay of iodne I ----> The graph shows how the mass of iodine-3 in a sample changes over a period of time. What is the half-life of this isotope?... days. (2) National 5 hemistry

7 20. Polystyrene is made from the monomer, styrene. The systematic name for styrene is phenylethene. (a) The monomer used to form polystyrene is shown. Which part of the structure of styrene allows the polymer to form? omplete the diagram to show how three styrene molecules join to form part of the polymer chain. (c) Give another name for polystyrene. (3) [ End of Question paper ] National 5 hemistry

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