JAMB UTME - Chemistry - 1979
Pregunta 2 Informe
Weighed salts Y and Z were left exposed in the laboratory overnight. In the morning Y had gained weight, and Z had become liquid. What conclusion could be drawn about the nature of the two salts?
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Pregunta 3 Informe
When carbondioxide is bubbled into limewater a white precipitate is formed. If the passage of the gas is continued, the precipitate disappears. The reason for this is
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Pregunta 4 Informe
Which are the correct IUPAC names for H-CO2CH3 and CH = CH
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Pregunta 5 Informe
The solution of a sample in a tube will be identified as a chloride if it gives
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The solution of a sample in a tube will be identified as a chloride if it gives a white precipitate when acidified with dilute HNO3 and then AgNO3 solution is added. This is because the test is a confirmatory test for chloride ions, and the white precipitate formed is silver chloride (AgCl). Chloride ions react with silver nitrate (AgNO3) to form a white precipitate of AgCl, which is insoluble in water and dilute nitric acid.
Pregunta 7 Informe
When ammonium, potassium and calcium carbonates are each separately heated
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Pregunta 8 Informe
A gas occupies 30.0 dm3 at S.T.P. What volume would it occupy at 91oC and 380 mm Hg?
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Pregunta 9 Informe
When excess ethanol is heated to 145 oC in the presence of concentrated sulphuric acid, the product is
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Pregunta 10 Informe
In the extraction of aluminum from purified bauxite by electrolysis, cryolite is used because
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Pregunta 11 Informe
Calcium hydroxide and ammonium chloride when heated together will give an important product. This compound may be obtained dry by
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Pregunta 12 Informe
How many grams of HBr would exactly be required to react with 2 g of propyne? (C =12, H=1, Br = 80)
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Pregunta 13 Informe
When a piece of charcoal enclosed in a cylinder containing air is ignited
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Pregunta 14 Informe
On heating anhydrous iron (ll) sulphate, in addition to producing iron (iii) oxide, which of the following is produced?
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Pregunta 15 Informe
Which of the following statements applies during the electroysis of sodium hydroxide sodium hydroxide solution using platinum electrodes?
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Pregunta 16 Informe
The reaction between hydrogen and iodine may be represented by the equation H2(g)+ I2(g) → 2HI(g), and is exothermic. Therefore
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Pregunta 17 Informe
The empirical formula of an oxide of nitrogen containing 30.4 per cent of nitrogen is (N=14.0,O=16.0)
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Pregunta 18 Informe
0.1 Faraday of electricity was passed through a solution of copper (ll) sulphate. The maximum weight of copper deposited on the cathode would be [Cu = 64]
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Pregunta 19 Informe
Indicate which of the following statements is not true as we move from left to right along the periodic Table:
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Pregunta 21 Informe
A piece of metal (M) is dissolved in nitric acid and the resulting solution is treated with a small quantity of sodium hydroxide to produce a white precipitate (B) which redissolves on the addition of excess alkali. The precipitate (B)when ignited in a crucible produces the oxide of the metal(m). The METAL M is
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Pregunta 23 Informe
Consider the following exothermic reaction 2SO2(g) + O2(g) = 2SO3 (g) . If the temperature of the reaction is reduced from 800oC to 500oC, and no other change takes place, then
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Pregunta 24 Informe
Which of the following raw materials would be required from the smelting of iron ore in a blast furnace?
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Pregunta 25 Informe
In the manufacture of iron in the blast furnace, iron (lll) oxide is mixed with coke and limestone, and different reactions occur in the process. Which of the following statements is true with respect to these reactions?
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Pregunta 29 Informe
Which one of these compounds will NOT give an oxygen gas on heating?
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Pregunta 31 Informe
Which of the structural formal above is ethanoic acid is
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Pregunta 32 Informe
Phosphorus burns in oxygen according to the equation P4 + 502 → P4O10. How many litres of oxygen will be required at S.T.P for complete oxidation of 12.4g of phosphorus? [P = 31,O = 16 and molar volume of a gas at S.T.P = 22.4 litres]
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Pregunta 33 Informe
In which of the following reactions is sulphur dioxide acting as an oxidizing agent?
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Pregunta 34 Informe
Which of the following substances are all made by the process of polymerization?
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Pregunta 35 Informe
The reaction of zinc with copper (ll) ions in aqueous solution can be represented as follows: Cu 2+(aq) +Zn (s) → Cu(s) + Zn 2+(aq).Which of the following is the most complete description of this reaction?
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Pregunta 38 Informe
If chlorine gas is bubbled into water and then this yellowish-green coloured solution is exposed to bright sunlight for a while
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Pregunta 39 Informe
12 g of solid protassium chlorate (KCIO) were added to 40 g of water and heated to dissolve all the solid. As the solution cools, crystals of potassium chlorate at 66 oC. The solubility of potassium chlorate at 66 oC is therefore
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Pregunta 40 Informe
Which of the following statements is true? When the potassium atom forms its ion
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Pregunta 41 Informe
An organic compound X has the following properties: I. It is not miscible with water. ll. lt has boiling point of 77oC lll. lt has a sweet odour lV. lt is insoluble in sodium hydrogen carbonate solution . V lt does not decolourize bromine water X is therefore
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Pregunta 42 Informe
In the electrolysis of dilute sulphuric acid using platinum electrodes, the products obtained at the anode and cathode are:
Anode Cathode
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Pregunta 43 Informe
One of the following techniques can be used to show that chlorophyll pigment is a mixture of chemical compounds and not a single coloured compound
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Pregunta 44 Informe
Methanoic acid mixes with water in all proportions and has about the same boiling point as water which of the following methods would you adopt to obtain pure water from a mixture of stand, water and methanoic acid?
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Pregunta 45 Informe
The oxidation state of manganese in potassium permanganate is
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Pregunta 47 Informe
The reaction 3C(s) + 2Fe2O3(s) = 4Fe(s) + 3CO2(g): \(\Delta\)H =46.0 kJ is
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Pregunta 48 Informe
\(50cm^{3}\) of hydrogen are sparked with \(20cm^{3}\) of oxygen at \(100°C\) and \(1atm\) . The total volume of the residual gases in
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