Our country, our future S2 CHEMISTRY DURATION: 2 HOUR

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1 Our country, our future S2 CHEMISTRY Exam 1 DURATION: 2 HOUR INSTRUCTIONS: This paper consists of two sections A and B, Attempt all questions in section A and B For section A, circle the most correct alternative All answers to section B should be written in the spaces provided SECTION A 1. Which one of the following substances will dissolve in water to give a solution that would turn red litmus paper blue? A. Sodium chloride C. Sodium hydroxide B. Sodium sulphate D. Sodium nitrate 2. Which one of the following liquids is mixable with water? A. Ethanol C. Kerosene B. Methylbenzene D. Petrol 3. What is the formula of an oxide of a compound whose hydroxide is X(OH) 3? A. XO 3 C. X 3O B. X 3O 2 D. X 2O 3 4. Which one of the following is not an acidic oxide? A. Sulphur dioxide C. Carbon monoxide B. Carbon dioxide D. Nitrogen dioxide 1. more Exams? Browse: digitalteachears.co.ug For consultations? Call

2 5. Green pigment in leaves can be separated by A. Distillation C. Sublimation B. Precipitation D. Chromatography 6. Which one of the following metals can displace zinc from zinc sulphate solution? A. Cu B. Pb C. Ca D. Ag 7. The electronic configuration of W, V, U, T and X are W(2:8:7), V(2:8:8:2), W(2:8:5), T(2:8:8:4), X(2:8:1). Which pair of elements is likely to form an alkaline solution when reacted with water? A. X and W C. U and X B. V and T D. V and X 8. Zinc oxide is A. An amphoteric oxide C. An acidic oxide B. A basic oxide D. A neutral oxide 9. Which of these is not a halogen? A. Fluorine B. Bromine C. Iodine D. Argon 10. Rust is hydrated A. Iron (ii) oxide C. Iron (ii) hydroxide B. Iron (iii) oxide D. Iron (iii) hydroxide 11. The following gases are NOT used in making electric light bulbs except A. Hydrogen B. Nitrogen C. Oxygen D. Argon 12. Which one of the following is not an alkaline? A. Cu(OH) 2 C. Ca(OH) 2 B. KOH D. NaOH 13. Element M has electronic configuration of 2:8:3, the most stable ion of M is A. M 3- B. M - C. M + D. M A colourless gas turns litmus paper red and lime water milky. The gas is likely to be A. Chlorine C. Carbon dioxide B. Sulphur dioxide D. Hydrogen sulphide 15. Which compound is used as a catalyst in the preparation of hydrogen gas? A. Manganese (iv) oxide C. Copper (ii) sulphate B. Hydrochloric acid D. Calcium sulphate 16. X is the most reactive metal. X is most likely to be; A. Aluminum C. Magnesium 2. more Exams? Browse: digitalteachears.co.ug For consultations? Call

3 B. Potassium D. Copper 17. The metal that reacts very slowly with cold water but vigorously with steam is; A. Potassium B. Gold C. Copper D. Magnesium 18. An efflorescent substance A. turns white anhydrous copper (ii) sulphate blue B. gives out water of crystallization to the atmosphere C. turns lime water milky D. absorbs water of crystallization from atmosphere 19. One of the following is NOT an example of a chemical change. A. heating a wire by electricity B. rusting of iron C. decomposing a substance by electricity D. Precipitation of a solid when two liquids are mixed 20. The following are products of burning organic substances. A. water and carbon dioxide B. Water and oxygen C. Calcium hydroxide and soda lime D. Lime water and copper (ii) sulphate 21. Which of the following non metals is most reactive? A. Sulphur B. Oxygen C. Nitrogen D. Chlorine 22. The valency of X in X 2(SO 4) 3 is A. 2 B. 3 C. 4 D In which group of the periodic table is element M found? A. I B. II C. III D. IV 24. The following properties are typical of alkali metals except. A. Have one electron in their outermost shell B. React with cold water to form alkaline solution C. Are good conductors of heat and electricity D. Are inert 25. Which one of the following electron structure will indicate the least reactive element? A. 2:8:1 B. 2:8:2 C. 2:8:7 D. 2:8:8 3. more Exams? Browse: digitalteachears.co.ug For consultations? Call

4 SECTION B 26. Define the following terms giving examples in each case (a) Isotope (b) Halogens (c) Chemical change (d) Catalyst (e) Fractional distillation 27. Write well balanced chemical equations for the following reactions. (a) Magnesium + Carbon dioxide Magnesium oxide + Carbon (b) Zinc sulphate + Sodium carbonate Zinc carbonate + Sodium sulphate (c) Calcium chloride + Sodium carbonate calcium carbonate + Sodium chloride 4. more Exams? Browse: digitalteachears.co.ug For consultations? Call

5 (d) Magnesium + Oxygen Magnesium oxide (e) Iron (iii) Oxide + Carbon monoxide Iron + Carbon dioxide 28. Part of the periodic table representing the positions of elements W, X and Z is shown below. I II III IV V VI VII VIII W X Z (a) Write the formula of the oxide of W. (01mark) (b) The oxide of W was dissolved in water. State whether the resultant solution is acidic, alkaline or neutral. Explain your answer and write equation for the reaction (03marks) (c) Write the formula f the compound formed between W and Z (01mark) (d) Which of the atoms W, X and Z has the largest atomic radius? (01mark) 5. more Exams? Browse: digitalteachears.co.ug For consultations? Call

6 (e) Write the symbols for the ions that the elements W, X and Z above will form. (03marks) (f) Write the formula of the sulphate formed by X. (01mark) 29. Air is mostly a mixture of two gases (a) (i) Name the two main gases (01mark) (ii) State the method that can be used to separate the two gases you have named in (a) (i) above (01mark) (iii) Give a reason for your answer in (a)(ii) above (01mark) (b) Give two reasons why air is considered a mixture and not a compound. 30. An atom of an element, atomic mass 31 contains 15 protons (a) (i) State the number of neutrons in X (01mark) (ii) Write the electronic configuration of X (01mark) 6. more Exams? Browse: digitalteachears.co.ug For consultations? Call

7 (iii) Draw a simple electronic structure of X (01marks) (b) State the group and period in the periodic table to which X belongs. Group (01mark) Period (c) Write the formula of the compound that can be formed between X and chlorine. (01mark) END 7. more Exams? Browse: digitalteachears.co.ug For consultations? Call