Second Term Examination
Class : SSS 1
Subject :Chemistry
Section A : Objective Tests
Instruction : Read the questions carefully and choose from the alternative lettered a – d.
1. All of the following are studied in chemistry except _________. (a) composition of matter (b) properties and uses of matter (c) principles governing changes in matter (d) transcendence of matter
2. These are adverse effects of chemistry except __________. (a) pollution (b) population (c) corrosion (d) drug abuse
3. All of these are examples of chemical Reactions except (a) rusting (b) sour soap (c) melting of candle wax (d) burning of substances
4. The element with the electronic configuration 2, 8, 4 is ________. (a) Al (b) Mg (c) P (d) Cl
5. Scientific approach to discoveries follows which of the following order? (a) further experiments and problem solving (b) theory, negative and positive results and experiments (c) experiments, hypothesis and result (d) observation, hypothesis and experiment
6. A ________ is established only after the theory has been extensively tested and proven to be true without any exception. (a) theory (b) hypothesis (c) law (d) modified theory
7. The addition of water to calcium oxide leads to _________. (a) a physical change (b) a chemical change (c) the formation of mixture (d) an endothermic change
8. Which of the following substance is not a homogenous mixture? (a) filtered sea water (b) soft drink (c) flood water (d) writing ink
9. Pure water is made to boil below 100°C under (a) decreased volume (b) increased volume (c) increased external pressure on it (d) decreased external pressure on it
10. Ice, water and steam (a) have the same physical properties (b) are different allotropes (c) are chemically alike (d) have different Mar masses
11. The addition of calcium carbide to water results to (a) a mixture (b) no change (c) a chemical change (d) a physical change
12. The separation of petroleum fractions depends on the difference in their (a) boiling point (b) molar masses (c) melting points (d) solubility
13. A solid can be obtained from its saturated solution by (a) filtration (b) crystallization (c) condensation (d) decomposition
14. One of these professions has no need for chemistry. (a) miners (b) engineers (c) geologists (d) philosophers
15. Which is the odd one? (a) Air (b) Urine (c) Brass (d) Sand
16. Sieving is a technique used to separate mixtures mixtures containing solid particles of (a) small sizes (b) large sizes (c) the same size (d) different sizes
17. When a solid substance disappears completely as a gas on heating the substance is said to have undergone (a) evaporation (b) distillation (c) crystallization (d) sublimation
18. A homogeneous mixture can be defined as a mixture __________. (a) whose composition is uniform (b) whose composition is not uniform (c) formed by solids and Liquids (d) of a solute and a solvent.
19. Sulphur has the atomic number of _______. (a) 15 (b) 16 (c) 17 (d) 18
20. Which of the following separation technique is used to separate solids of relative magnetizability? (a) centrifugation (b) Evaporation (c) Fractional crystallization (d) Distillation
Section B: Theory
Attempt all questions.
1. Mention five differences between a mixture and a compound.
2. Classify the following into elements, compounds and mixtures: limestone, diamond, and, soil, urine, bronze, sugar, gold, clay, urea, soap, milk, air, neon and iron.
3. Mention five differences between metals and non-metals.
4. How would you separate any of the components in the pure form from each of the following mixtures:
i. A mixture of sodium chloride and ammonium chloride
ii. A mixture of anhydrous sodium trioxocarbonate (iv) and sodium hydrogen trioxocarbonate (iv)
iii. A mixture of iron dust and zinc dust
iv. A mixture of water and sugar
V. A mixture of sodium chloride and potassium trioxonitrate (V)
vi. A mixture of chlorine and hydrogen chloride gas.