JAMB UTME - Chemistry - 1983
Ibeere 1 Ìròyìn
An unknown organic compound X has a relative molecular mass of 180. It is a colourless crystaline solid, readily soluble in water. X contains the elements C, H and O in the atomic ratio 1: 2:1. The compound has a sweet teste and melts on heating. In the presence of yeast and in the absence of air, X is converted to compound Y and a colourless gas. Compound Y reacts with sodium metal to produce a gas Z which gives a 'pop' sound with a glowing splint. Y also reacts with ethanoic acid to give a sweet smelling compound W.
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Ibeere 2 Ìròyìn
In the reaction Fe + Cu2+ → Fe2+ + Cu,iron displaces copper ions to from copper. This is due to the fact that
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Ibeere 5 Ìròyìn
zn + 2HCl → ZnCl2 + H2The rate of the above reaction will be greatly increased if
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Ibeere 6 Ìròyìn
How many isomeric forms are there for the molecular formula C3H6Br2?
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Ibeere 7 Ìròyìn
In the reactions
(I) H2 (g) + 1/2O2(g) → H2O(l); ∆H = -286 KJ
(II) C(s) + O2g) → CO2 (g); ∆H = -406 KJ the equations imply that
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Ibeere 8 Ìròyìn
In the experiment above, a current was passed for 10 minutes and 0.63g of copper was found to be deposited on the cathode of CuSO4 cells. The weight of silver deposited on the cathode og AgNO3 cell during the same period would be? [Cu = 63, Ag = 108]
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Ibeere 9 Ìròyìn
Liquid X, reacts with sodium trioxocarbonate (IV) (Na2CO3) to give a gas which turns calcium chloride solution milky X is
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Ibeere 10 Ìròyìn
A piece of burning sulphur will continue to burn in a gas jar of oxygen to give misty fumes which readily dissolved in water. The resulting liquid is
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Ibeere 11 Ìròyìn
X is a crystalline salt of sodium solution of X in water turns litmus red and produces a gas which turns lime water milky when added to sodium carbonate. With barium chloride solution, X gives hydrochloric acid. X is
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Ibeere 15 Ìròyìn
In the reaction M + N P;∆H = + QKJ. Which of the following would increase the concentration of the product?
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Ibeere 16 Ìròyìn
An unknown organic compound X has a relative molecular mass of 180. It is a colourless crystaline solid, readily soluble in water. X contains the elements C, H and O in the atomic ratio 1: 2:1. The compound has a sweet teste and melts on heating. In the presence of yeast and in the absence of air, X is converted to compound Y and a colourless gas. Compound Y reacts with sodium metal to produce a gas Z which gives a 'pop' sound with a glowing splint. Y also reacts with ethanoic acid to give a sweet smelling compound W.
The molecular formula of X is
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Ibeere 17 Ìròyìn
Which of the following solutions will give a white precipitate with barium chloride solution and a green flame test?
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Ibeere 19 Ìròyìn
Which volume of 0.5 M H 2SO4 will exactly neutralize 20 cm 3 of 0.1 M NaOH solution?
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CAVACbVb=12
frac0.5×VA0.1×20=12
\(V_A = \frac{0.1 \times 20}{2 \times 0.5} = \frac{1.0}{0.5)\)
= 2cm2
Ibeere 22 Ìròyìn
30 cm3 of 0.1 M Al (NO3)3 SOLUTION IS RECTED WITH 100cm3 of 0.15M of NaOH solution. Which reactant is in excess, and by now much ?
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Ibeere 23 Ìròyìn
The cracking process is very important in the petroleum industry because it.
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Ibeere 24 Ìròyìn
Some metals are extracted from their ores after some preliminary treatments by electrolysis (L), some of both processes (TL). Which set-up in the following for the extraction of ion, copper and aluminium is correct?
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Ibeere 25 Ìròyìn
Sodium sulphate decahydrate (Na2SO4.10 H2O) on exposure to air loses all its water of crystallization.
The process of loss is known as
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Ibeere 26 Ìròyìn
Which of the following happens during the electrolysis of molten sodium chloride?
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Ibeere 27 Ìròyìn
Which of the following relationships between the pressure P, the volume V and the temperature T, represents an ideal gas behaviour?
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Ibeere 28 Ìròyìn
Some copper (ll) sulphate pentahydrate (CuSO4 5H2O), was heated at 120 oC with the following results. Wt of crucible = 10.00 g; Wt of crucible + CuSO4 5H2O =14.98g; Wt of crucible + residue = 13.54 g. How many molecules of water of crystalization were lost?
[H = 1, Cu = 63.5, O = 16, S = 32]
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CuSO4 + 5H 2O
Wt CuSO4 + 5H2O = 14.98 - 10.00
= 4.98 gm
Wt of residue or CuSO4 = 13.54 - 10.00 =3.54
Wt of water lost = 4.98 - 3.54 = 1.44
Molecules of H2O lost = 5 - 1 = 4
Ibeere 29 Ìròyìn
Which of these metals, Mg, Fe, Pb and Cu will dissolve in dilute HCI?
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Ibeere 30 Ìròyìn
In which of the following processes is iron being oxidized?1 Fe + H2SO4 → FeSO4 +H22 FeSO4 + H2S → FeS + H2SO43 2FeCI2 + Cl2 → 2FeCl34 2FeCl3 + SnCl2 + → 2FeCl2 + SnCl4
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Ibeere 31 Ìròyìn
A mixture of common salt, ammonium chloride and barium sulphate can best be separated by
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Ibeere 32 Ìròyìn
An unknown organic compound X has a relative molecular mass of 180. It is a colourless crystaline solid, readily soluble in water. X contains the elements C, H and O in the atomic ratio 1: 2:1. The compound has a sweet teste and melts on heating. In the presence of yeast and in the absence of air, X is converted to compound Y and a colourless gas. Compound Y reacts with sodium metal to produce a gas Z which gives a 'pop' sound with a glowing splint. Y also reacts with ethanoic acid to give a sweet smelling compound W.
Reaction of X with yeast forms the basis of the
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Ibeere 33 Ìròyìn
Zn + H2 SO4 → ZnSO4 + H2
In the above reaction how much Zinc will be left of 1.0 M of H2SO?
[Zn =65, s = 32, O = 16, H = 1]
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Ibeere 34 Ìròyìn
The equilibrium reaction between copper (l) chloride and chlorine at 25oC and 1 atmosphere is represented by the equation:
2CuCl +Cl2 ⇌ 2 CuCl2 ∆H = - 166 KJ. Which of the following statements is TRUE for the reaction, pressure remaining constant?
Ibeere 35 Ìròyìn
In the preparation of some pure crystals of Cu (NO3)2 starting with CuO, a student gave the following statements as steps he employed. Which of these shows a flaw in his report ?
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Ibeere 36 Ìròyìn
A jet plane carrying 3,000 kg of ethane burns off all the gas forming water and carbondioxide. if all the carbondioxide is expelled and all the water formed is condensed and kept on board the plane, then the gain in weight is
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Ibeere 37 Ìròyìn
3. 06 g of a sample of potassium trioxochlorate (V) (KCIO) was required to make a saturated solution with 10cm3 of water at 25oC. The solubility of the salt at 25oC is [K =39, Cl = 35.5, O = 16]
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Ibeere 38 Ìròyìn
Which of the following separation processes is most likely to yield high quality ethanol (>95%) from palm wine?
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Ibeere 39 Ìròyìn
Which of the following pair of gases will NOT react further with oxygen at a temperature between 30oC AND 400oC
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Ibeere 40 Ìròyìn
When sodium dioxonitrate (lll) (NaNO2) dissolves in water, ∆H is positive. The process of dissolution is
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Ibeere 43 Ìròyìn
2.5 g of a hydrate barium salt gave on heating, 2.13 g of the anhydrous salt. Given that the relative molecular mass of the of the anhydrous salt is 208, the number of molecules of water of crystallization of the barium salt is
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Ibeere 44 Ìròyìn
C2H5 - C = CH2
CH3The correct name of the compound with the above structural formula is
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Ibeere 45 Ìròyìn
Crude petroleum pollutant usually seen on some Nigerian creeks and waterways can be dispersed or removed by
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Ibeere 48 Ìròyìn
Solutions X, Y, and Z have PH values 3.0. 5. 0 and 9. 0 respectively. Which of the following statements is correct?
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