JAMB UTME - Chemistry - 1986

20 cm3 of 1.0 molar NH4OH solution when neutralized with 20.05cm3 of 0.1 molar HCl liberated -102 joules of heat. Calculate the heat of neutralization of NH4OH?

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NH4OH = 20cm of 0.1 m
NH4 + HCl → NH4Cl = H2O
Heat of Neutralization of NH4OH
= $\frac{-102}{2}$ = -51.0 KJ mole-1

When steam is passed through red hot carbon, which of the following are produced?

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Which of the following is an acidic salt?

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Which of these represents a redox reaction?

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The approximate volume of air containing 10cm3 of oxygen is?

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Volume of air containing 10 cm O2 is
(100 x 10)/(20) = 50cm3

How many coulombs of electricity are passed through a solution in which 6.5 amperes are allowed to run for 1.0 hour?

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How will a metal X, which reacts explosively with air and with dilute acids be best extracted from its ores?

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When ethanol is heated with excess concentrated sulphuric acid, the ethanol is?

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The exhaust fumes from a garage in a place that uses petrol of high sulphur content are bound to contain?

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A white solid suspected to be lead trioxonitrate (V) zinc trioxocarbonate (IV) or calcium trioxocabonate (IV) was heated strongly. Its residue which was yellow when hot and white when cold is?

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The movement of liquid molecules from the surface of the liquid to the gaseous phase above it is known as?

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Which of the following are made by the process of polymerization?

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Which of the following solutions will conduct the least amount of electricity?

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How much of magnesium is required to react with 260cm3 of 0.5 M HCl? [Mg = 24]

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Which of the following metals does NOT form a stable trioxocarbonate (IV)?

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Which of the following does NOT contain aluminium as component?

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Which of the following sulphides is insoluble in dilute HCl?

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In the electrolysis of aqueous solution of K2SO 4 in the above cell, which species migrate to the anode?

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10cm3 of hydrogen fluoride gas react with 5cm3 of dinitrogen difluoride gas (N2F2) to form 103 of a single gas. Which of the following is the most likely equation of the reaction?

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When chlorine is passed into water and subsequently exposed to sunlight, the gas evolved is?

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In the solubility curve above, water at 98oC is saturated with KCL and KCIO3 What is the percentage of KCL impurity in the crystals formed when the solution is cooled to 30 oC?

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Which of the following groups of physical properties increases from left to right of the periodic table? i. Ionization energy ii. Atomic radius iii. Electronegativity iv. Electro affinity

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In the course of an experiment, two gases X and Y were produced. X turned wet lead ethanoate to black and Y bleached moist litmus paper. What are the element(s) in each of the gases X and Y respectively?

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The reaction Mg + H2O → MgO + H2 takes place only in the presence of?

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The relationship between the velocity (U) of gas molecules and their relative molecular mass (M) is shown by the equation

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The relationship between (U) of a gas molecule and the relative molecular mass is $\overline{U}$ = ($\frac{k}{m}$)${}^{\frac{1}{2}}$

or $\overline{U}$ = $\sqrt{k}m$

An element with atomic number twelve is likely to be

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A substance Z reacts with NaOH to give salt and water only. When Z is treated with dilute HCl, a gas is evolved which gives a yellow suspension on passing into concentrated H2SO4. Substance Z is?

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Which of the following compounds would give lilac flame coloration and a white precipitate with acidified barium chloride solution?

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What reaction takes place when palm-oil is added to potash and foam are observed?

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Which of the following substances is a mixture?

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The general formula of an alkyl halide (where X represents the halide) is?

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Use the options above to answer this question. Which is the structural formula for pent-2-enoic acid?

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The iron (III) oxide impurity in bauxite can be removed by?

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What is the consequences of increasing pressure on the equilibrium reaction ZnO(s) + H2(g) Zn(s) + H2O(I)?

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What are the values of x, y and z respectively in the equation: xCu + yHNO3 ? xCu(NO3)2 + 4H2O + zNO?

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The number of atoms of chlorine present in 5.85g of NaCl is [Avogaro's Number = 6.02 x 1023]

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The number of atoms of chloride present in 5.85g of NaCl is 5.85 x 6.0 x 1023

= 6.02 x 1022

Oxygen-demanding waste are considered to be a water pollutant because they?

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Which of the following compounds is NOT formed by the action of chlorine on methane?

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Ammonia gas is normally dried with?

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Which of the following will react further with oxygen to form higher oxide?

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When 50cm3 of a saturated solution of sugar (molar mass 342.0g) at 40oC was evaporated to dryness, 34.2g of dry solid was obtained. The solubility of sugar at 40oC is

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What mass of a divalent metal M (atomic mass = 40) would react with excess hydrogen gas measured at S.T.P?

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Which of the following is used as an 'anti-knock' in automobile engines?

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Which of the following is NOT correct test for the named organic compound in each case?

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The tabulated results below were obtained by titration 10.0 cm3 of water with soup. The titration was repeated with the same sample of water after boiling. The ratio of permanent to temporary hardness is

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The ratio of permanent to temporary hardness will be 20:(20 - 15)

= 20:5

= 4:1

Starch can be converted to ethyl alcohol by?

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Which of the following salts when dissolved in water will NOT give the corresponding pH value?

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