JAMB UTME - Chemistry - 1981

If concentrated sulphric acid is added to sugar and warmed gently, the sugar changes from white to brown and finally to a black mas of carbon. In this reaction, concentrated sulphuric acid is acting as ?

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The oxidation number of manganese in KMnO₄ is?

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When glowing splint is inserted into the mouth of a jar containing a gas, the splint is extinguished. The gas gives a white precipitate when passing into barium hydroxide. The gas is?

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Which of the following compounds and elements would sublime on exposure to the atmosphere?

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Which of the following is NOT a true statement of the kinetic Theory of Gases?

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What mass of sodium carbonate solution is in 500 cm³ of 0.1 molar sodium carbonate solution?

(Na = 23, C = 12, O = 16)

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If an organic compound decolorizes bromine water then the compound is?

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In the preparation of ammonia, which of the following is used as the drying agent?

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The brown coloration in nitric acid prepared in the laboratory can be removed by?

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Allotropes are elements having?

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When air is compressed?

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Na₂CO₃ + 2HCI → 2NaCI + H₂O + CO₂. Using the above equation, what volume of carbondioxide, measured at s.t.p is liberated when 53g of sodium carbonate is dissolved in hydrochloric acid?
(1 mole of gas occupies 22.4 dm³ at s.t.p)
(Na = 23, C = 12, O = 16)

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When sodium nitrate dissolves in water, ∆H is positive. This means that?

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In the reaction
C + 2HNO₃ → CO₂ + NO₂ + NO + H₂O nitric acid is acting as?

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An efflorescent compound is a substance that?

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Fats and oils are?

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When hydrogen sulphide and sulphur dioxide are each passed in turn into a solution of potassium dichromate?

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The mass number of an atom is?

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Oxidation is the process of?

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28.8 cm³ of nitrogen at 15°C is cooled to O°C at constant pressure, the new volume of nitrogen is?

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Which of the following represents a precipitation reaction?

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If one mole of aluminium contains 6 x 10²³ atoms of aluminium, how many atoms are contained in 0.9g of aluminium?
(Al = 27)

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The products of the reaction between dilute sulphuric acid and sodium thiosulphate crystals are?

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Which of the following is the electronic configuration of sodium?
(Atomic number of Na = 11)

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Pure sulphuric acid is a liquid of 1:84 density. What volume of it would be required to prepare 250 cm³ of 2.0 M solution?



(H = 1, S = 32, O = 16)

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Sodium and potassium belong to the same group of the Periodic Table. This is because?

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What happens when the nitrates of potassium, calcium, zinc and copper are separately heated?

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Which of the following processes takes place during electrolysis?

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For iron to rust, there should be present?

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Methane is member of the homologous series called?

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5cm³ of a saturated solution of sodium chloride at 30°C gave, on careful evaporation, 1.95g of solid salt. The solubility of sodium chloride at 30°C?

(Na = 23, Cl = 35.5)

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An element X has 127 neutrons and 82 electrons.
Its atomic number is?

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If 48,000 coulombs of electricity are required to discharge 0.5 mole of sodium from a molten sodium chloride mass, then the number of coulombs required to discharge 2 moles of lead from molten lead (ll) chloride is?

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The general formula of an alkyl halide (which represent the halide) is?

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the number of atoms in one mole of a substance is equal to?

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When a bottle of Coca-Cola is opened, bubbles of evolve. The gas is?

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The electronic configuration of elements X and Y are X = 2, 8, 6; Y = 2, 8, 7. The bond in the compound formed by X and Y is expected to be?

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The scale formation in a kinetic used for boiling water is caused by the presence in water of?

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The IUPAC name for

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Which one of the following metals is not normally extracted by chemical reduction because of its position in the electrochemical series?

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In the reaction of oxygen with hydrogen to produce water, which of the following statements is true?

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Which of the following statements about phosphorus is NOT correct?

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A polymerization reaction is one in which?

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Which of the following statements is NOT true of electrovalent compounds?

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An example of a strong electrolyte is?

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The following compounds are given with their corresponding boiling points.
Compound Boiling Point
i.................................14°C
ii................................24°C
iii................................0°C
iv................................120°C
V.................................-2°C
From the above information, indicate which of the following is correct?

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In the extraction of iron, which of the following reactions does NOT take place in the blast furnace?

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4g each of aluminium foil and aluminium powder were introduced respectively into flasks P and Q.
Flask P was treated with warm bench sodium hydroxide and all the aluminium dissolved in one hour. Flask Q was treated with cold sodium hydroxide and all the aluminium dissolved in 10 minutes. What was responsible for Q reacting faster than P?

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Which of the following can have an isomer?

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