JAMB UTME - Chemistry - 1987

The times taken for iodine to be liberated in the reaction between sodium thiosulphate and hydrochloric acid at various temperature are as follows. These results suggest that

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The best treatment for a student who accidentally poured concentrated tetraoxosulphate (VI) acid on his skin in the laboratory is to wash the skin with?

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Ethanol reacts with aqueous sodium mono-oxoio date (l) to give a bright yellow solid with a characteristic smell. The product is?

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The greater the different in electronegativity between bonded atoms, the?

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When sodium hydroxide is heated with ammonium tetraoxosulphate (IV), the gas given off may be collected by?

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Magnesium ribbon was allowed to burn inside a given gas P leaving a white solid residue Q. Addition of water to Q liberated a gas which produced dense white fumes with a drop of hydrochloric acid. The gas P was?

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The efficiency of petrol as a fuel in high-compression internal combustion engines improves with an increase in the amount of?

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Use the option above to answer this question. The structure of benzoic acid is

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The most volatile fraction obtained from fractional distillation of crude petroleum contains?

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If d represents the density of a gas and K is a constant, the rate of gaseous diffusion r is related to d by the equation?

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r = k /√d

An element Z, contained 90% of 168Z and 10% of Z1818 its relative atomic mass is?

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Mass number of Z = 16 while that of Z is 18
90 x 16 = 14.4 10 x 18 = 1.8
100 1 100 1
it relative atomic mass = 14.4 + 1.8 = 162

If 24.83 cm3 of 0.15 M NaOH is titrated to its end point with 39.45 cm3 of HCl, what is the molarity of the HCl?

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NaOH + HCl → NaCl + H2O moles ratio = 1/1
↔ (MaVa) / Mb x 39.45 = 0.094

Use the option above to answer this question. Which is the correct set of results for tests conducted respectively on fresh lime juice and ethanol.

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When water drops are added to calcium carbide in a container and the gas is passed through a jet and lifted, the resultant flame is called an?

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Complete oxidation of propan -1- ol gives?

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Alloys are best prepared by?

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Oil spillage in ponds and creeks can be cleaned up by?

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The reaction between sulphur (IV) oxide and oxygen is represented by the equilibrium reaction 2SO2(g) + O2(g) ↔ 2SO3(g), ∆H = -196 kJ. What factor would influence increased production of SO3(g)?

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The solubility of Na3AsO4(H2O)12 is 38.9g per 100g H2O. What is the mass percentage of Na3AsO4 in the saturated solution?

(As = 75, Na = 23, O = 16, H = 1)

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An isotope has an atomic number of 17 and a mass number of 36. Which of the following gives the correct number of neutrons and protons in an atom of the isotope?

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Mass number = number of protons + number of neutrons
36 = 17 + X; X = 36 -17 = 19
19 neutrons and 17 protons

Corrosion is exhibited by

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Synthetic rubber is made by polymerization of?

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A stream of air was successively passed through three tubes X, Y and Z containing a concentrated aqueous solution of KOH, red hot copper powder and fused calcium chloride respectively. What was the composition of the gas emanating from tube Z?

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Local black soap is made by boiling palm oil with liquid extract of ash. The function of the ash is to provide the?

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In which of the following pairs of element is allotropy exhibited by each element?

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Which of the following gases can best be used for demonstrating the fountain experiment?

I) Nitrogen (ii) Ammonia (iii) Nitrogen (I) oxide

(iv) Hydrogen chloride.

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In which of the following are the aqueous solutions of each of the substances correctly arranged in order to decreasing acidity?

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In the purification of town water supply, alum is used principally to?

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The atomic numbers of two elements X and Y are 12 and 19 respectively. The bond of these two elements is?

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Inspite of the electronic configuration, 1s22s22p2, carbon is tetraavalent because?

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both the 2s and 2p orbitals hydrodizes

Stainless steel is an alloy of?

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Which of the following elements will form oxide which will dissolve both in dilute HNO3 and NaOH solutions to form salts?

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Which of the following water samples will have the highest titre value when titrated for the Ca2+ ions using soap solution?

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Which of the following compounds will give a precipitate with an aqueous ammoniacal solution of copper (l) chloride?

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HC = C-CH2CH3