C. H⁺ + OH⁻ → H₂O D. Na⁺ + Cl⁻ → NaCl (viii) Which of the following chemical species have the same number of electrons? A. K⁺, Ca²⁺, Cl⁻, and Ar B. Cl⁻, Be²⁺, and O²⁻ C. O²⁻, Mg²⁺ D. Na⁺, Mg²⁺, Be²⁺, and Li⁺ (ix) A pipette is used for: A. Measuring distance or length B. Measuring specific volume of liquids C. Measuring volumes D. Heating liquid (x) The process of chlorination in water treatment aims at: A. Killing micro-organisms B. Syrup making C. Forming suspension D. Removing bad odours

Match each item in List A with a correct response in List B by writing its letter against the appropriate statement in the space provided. LIST A LIST B (i) ... is a non-metal oxide which combines with water to form an acid A. Mercuric oxide (ii) ... determines the arrangement of orbital electrons of an atom B. Efflorescent (iii) ... is the addition of hydrogen to or removal of oxygen from a substance C. Air (iv) ... loses water of crystallization at room temperature D. Data analysis (v) ... Is a gas heavier than air, does not support combustion and extinguishes flames E. Bonding (vi) ... Shows both acidic and basic properties F. Valency (vii) ... is used to test the presence of water in a substance G. Hydrogen oxide (viii) ... is the way by which atoms become stable H. Electronic configuration (ix) ... Is a mixture of gases I. Washing soda (x) ... the modern scientific procedure J. Carbon dioxide K. Zinc oxide L. Combustion M. Sulfur dioxide N. Reduction O. Anhydrous copper sulphate

1. ... is a non-metal oxide which combines with water to form an acid (1 alama)
2. ... determines the arrangement of orbital electrons of an atom (1 alama)
3. ... is the addition of hydrogen to or removal of oxygen from a substance (1 alama)
4. ... loses water of crystallization at room temperature (1 alama)
5. Is a gas heavier than air, does not support combustion and extinguishes flames (1 alama)
6. Shows both acidic and basic properties (1 alama)
7. is used to test the presence of water in a substance (1 alama)
8. is the way by which atoms become stable (1 alama)
9. Is a mixture of gases (1 alama)
10. the modern scientific procedure (1 alama)

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3. (a) What is matter? (b) Mention three (3) states of matter. (c) Write the names of the following processes of changing matter from one state to another: (i) Solid to liquid: (ii) Liquid to gas: (iii) Gas to liquid:

1. What is matter? (1 alama)
2. What is matter? (2 alama)
3. Mention three (3) states of matter. (3 alama)
4. Mention three (3) states of matter. (2 alama)
5. Write the names of the following processes of changing matter from one state to another: (4 alama)
6. Gas to liquid: (1 alama)

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4. (a) Write the chemical symbols for the following: (i) Lead: (ii) Potassium: (iii) Gold: (iv) Sodium: (v) Chlorine: (b) Write the formulae for the following compounds: (i) Carbon tetrachloride: (ii) Magnesium oxide: (iii) Aluminum sulphate: (iv) Ammonia: (v) Nitrogen dioxide: (c) Write balanced equations for the following chemical reactions: (i) Iron + Sulphate → Iron sulphate (ii) Decomposition of calcium carbonate (iii) Magnesium hydroxide + Hydrochloric acid → Magnesium chloride + H₂O (iv) Silver nitrate + Sodium chloride → Silver chloride + Sodium nitrate (v) Potassium + Sulphuric acid → Potassium sulphate + Hydrogen gas

1. Write the chemical symbols for the following: (5 alama)
2. Write the formulae for the following compounds: (5 alama)
3. Write balanced equations for the following chemical reactions: (5 alama)
4. Sodium: (1 alama)
5. Chlorine: (1 alama)
6. Ammonia: (1 alama)
7. Nitrogen dioxide: (1 alama)
8. Magnesium hydroxide + Hydrochloric acid → Magnesium chloride + H₂O (2 alama)

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(a) Define the term indicator. (b) Name the colours of indicators when they are in acidic or alkaline solution. INDICATOR ACID SOLUTION ALKALINE SOLUTION (i) Methyl Orange (MO) ................................ ................................ (ii) Litmus ................................ ................................ (iii) Phenolphthalein (POP) ................................ ................................ (c) Find the oxidation state or number of the following underlined elements: (i) Mg: ............................................................ (ii) NO₃⁻ (N underlined): ............................................................ (iii) SO₂ (S underlined): ............................................................ (iv) Na₃PO₄ (P underlined): ............................................................

1. Define the term indicator. (2 alama)
2. Name the colours of indicators when they are in acidic or alkaline solution. INDICATOR ACID SOLUTION ALKALINE SOLUTION (i) Methyl Orange (MO) ................................ ................................ (ii) Litmus ................................ ................................ (iii) Phenolphthalein (POP) ................................ ................................ (6 alama)
3. Find the oxidation state or number of the following underlined elements: (i) Mg: ............................................................ (ii) NO₃⁻ (N underlined): ............................................................ (iii) SO₂ (S underlined): ............................................................ (iv) Na₃PO₄ (P underlined): ............................................................ (2 alama)

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(a) Element A and B in the Periodic Table have atomic numbers 12 and 13 respectively. (i) Which element has a higher ionization energy? ........................................................................................................................................................................ .................................................................................................................................. (ii) Of the two elements, which one has smaller atoms? ........................................................................................................................................................................ .................................................................................................................................. (iii) Which type of bond forms when element A combines with chlorine? ........................................................................................................................................................................ 5 Candidate's Examination Number ………………… .................................................................................................................................. (iv) Find the charge of atom A after the reaction in question (iii). ........................................................................................................................................................................ .................................................................................................................................. (b) Mention four methods of preventing rusting. ......................................................................................................................................................................... ................................................................................................................................................. (c) Define the following: (i) Acid: ............................................................ (ii) Base: ............................................................

1. Element A and B in the Periodic Table have atomic numbers 12 and 13 respectively. (i) Which element has a higher ionization energy? ........................................................................................................................................................................ .................................................................................................................................. (ii) Of the two elements, which one has smaller atoms? ........................................................................................................................................................................ .................................................................................................................................. (iii) Which type of bond forms when element A combines with chlorine? ........................................................................................................................................................................ (iv) Find the charge of atom A after the reaction in question (iii). (4 alama)
2. Mention four methods of preventing rusting. ......................................................................................................................................................................... ................................................................................................................................................. (4 alama)
3. Define the following: (i) Acid: ............................................................ (ii) Base: ............................................................ (2 alama)

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Write three differences between a mixture and a compound.

1. Water mixed with kerosene: (0 alama)
2. Which method would you use to separate each of the following mixtures? (i) Water mixed with kerosene: ............................................................ (ii) Iron powder mixed with sand: ............................................................ (iii) Ammonium chloride crystals mixed with sodium chloride crystals: ............................................................ (iv) Water mixed with alcohol: ............................................................ (4 alama)
3. Write three differences between a mixture and a compound. ......................................................................................................................................................................... ................................................................................................................................................. (6 alama)
4. Iron powder mixed with sand: (0 alama)
5. Ammonium chloride crystals mixed with sodium chloride crystals: (0 alama)
6. Water mixed with alcohol: (0 alama)

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What is the use of the following apparatus? (i) Sandbath: (ii) Dropper: (iii) Tripod stand: (iv) Pipette: (v) Desiccator:

1. Sandbath: (0 alama)
2. Classify each of the following chemical equations as displacement, combination, neutralization, deposition, or decomposition: (i) BaCl₂(aq) + ZnSO₄(s) → BaSO₄(s) + ZnCl₂(aq): ............................................................ (ii) N₂(g) + 3H₂(g) → 2NH₃(g): ............................................................ (iii) 2Na(s) + 2HCl(aq) → 2NaCl(aq) + H₂(g): ............................................................ (iv) CaO(s) + 2HCl(aq) → CaCl₂(aq) + H₂O(l): ............................................................ (v) CuCO₃(s) → CuO(s) + CO₂(g): ............................................................ (5 alama)
3. What is the use of the following apparatus? (i) Sandbath: ............................................................ (ii) Dropper: ............................................................ (iii) Tripod stand: ............................................................ (3 alama)
4. Dropper: (0 alama)
5. Tripod stand: (0 alama)
6. Pipette: (0 alama)
7. Desiccator: (0 alama)

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Define the following: (i) Acid: (ii) Base:

1. Acid: (0 alama)
2. Base: (0 alama)

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What do you understand by the following chemical warning terms? (i) Explosive: (ii) Toxic: (iii) Flammable: (iv) Harmful:

1. Explosive: (0 alama)
2. Toxic: (0 alama)
3. Flammable: (0 alama)
4. Harmful: (0 alama)

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