JAMB UTME - Chemistry - 1987
Ibeere 1 Ìròyìn
Inspite of the electronic configuration, 1s22s22p2, carbon is tetraavalent because?
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both the 2s and 2p orbitals hydrodizes
Ibeere 2 Ìròyìn
The greater the different in electronegativity between bonded atoms, the?
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Ibeere 3 Ìròyìn
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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Ibeere 4 Ìròyìn
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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Ibeere 5 Ìròyìn
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
Ibeere 6 Ìròyìn
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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Ibeere 9 Ìròyìn
The most volatile fraction obtained from fractional distillation of crude petroleum contains?
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Ibeere 10 Ìròyìn
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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Ibeere 12 Ìròyìn
Which of the following compounds will give a precipitate with an aqueous ammoniacal solution of copper (l) chloride?
Ibeere 13 Ìròyìn
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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Ibeere 15 Ìròyìn
When sodium hydroxide is heated with ammonium tetraoxosulphate (IV), the gas given off may be collected by?
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Ibeere 16 Ìròyìn
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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Ibeere 17 Ìròyìn
In which of the following pairs of element is allotropy exhibited by each element?
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Ibeere 19 Ìròyìn
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
Ibeere 20 Ìròyìn
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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Ibeere 21 Ìròyìn
Use the option above to answer this question. The structure of benzoic acid is
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Ibeere 22 Ìròyìn
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?
Ibeere 24 Ìròyìn
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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Ibeere 25 Ìròyìn
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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Ibeere 26 Ìròyìn
In the purification of town water supply, alum is used principally to?
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Ibeere 27 Ìròyìn
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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Ibeere 28 Ìròyìn
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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Ibeere 29 Ìròyìn
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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Ibeere 30 Ìròyìn
| Temp (°C) | 25 | 35 | 45 |
| Time (seconds) | 72 | 36 | 18 |
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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Ibeere 31 Ìròyìn
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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Ibeere 32 Ìròyìn
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
Ibeere 33 Ìròyìn
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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