JAMB UTME - Chemistry - 2008
Frage 1 Bericht
The product obtained when a mixture of benzene vapour and hydrogen are passed over nickel catalyst at 180oC is
Frage 2 Bericht
Which of the following compounds of trioxonitrate (V) will decomposes to give dinitrogen (i) oxide and water when heated?
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Frage 3 Bericht
The oxidation state of carbon in HCOOH is
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HCOOH
O.N of H + O.N of C + 2* O.N of oxygen of
H = 0
1 + X + 2X - 2 + 1 = 0
2 + X -4 = 0
X = 4 - 2 = +2
Frage 5 Bericht
In countries where the temperature falls below 273K, salt is always sprinkled on the icy road in order to
Frage 6 Bericht
Chlorophyll obtained from given leaves of plant can be shown to be composed of more than one coloured component by the technique of
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Frage 8 Bericht
Reduction of alkanonoes with LialH4 produces
Frage 10 Bericht
If glucose is heated with concentration tetraoxosulphate (VI) acid, it will be dehydrated to
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Frage 11 Bericht
The substance that is used in the steel industry for the removal of carbon, sulphur and phosphorus impurities from pig iron is
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Frage 12 Bericht
If the silver mirror test is positive, it indicates the presence of an
Frage 13 Bericht
Choose the correct option from the structure above
Frage 14 Bericht
When a few drops of water is added to a blue anhydrous cobalt (II) chloride, the colour changes to
Frage 15 Bericht
If a given quantity of electricity liberates 0.65g of Zn2+, what amount of Hg2+ would be liberated by the same quantity of current?
[Zn = 65, Hg = 201]
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Frage 16 Bericht
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The correct answer is 11.
pH = -log(H+) Or 14 - pOH
pOH = -log(0.001)
pOH = 3
pH = 14 - 3 = 11
Frage 18 Bericht
In recharging a lead-acid accumulator, the reaction at the cathode can be represented as
Frage 20 Bericht
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Frage 21 Bericht
16.8 g of sodium hydrogen trioxocarbonate (IV) is completely decomposed by heat. Calculate the volume of carbon(IV) oxide given off s.t.p
[Na 23, C = 12, O = 16, H = 1, Molar volume of a gas at s.t.p = 22.4 dm3]
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2NaHCO3(s) → Na2CO3(s) + H2O(l) + CO2
Relative molecular mass of NaHCO3 = 23 +1 + 12 + 16 * 3 = 84smol-1
2 * 84g of NaHCO3 will be liberated 22.4dm3 or CO2 at s.t.p
16.8g of NaHCO3 will libertae (16.8 * 22.4)/(2 * 84) = 2.24 dm3
Frage 22 Bericht
NH3(g) + HCl(s) → NH4Cl(s)
The entropy change in the system above is
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Frage 23 Bericht
The IUPAC nomenclature for the structure above is
Frage 25 Bericht
1111Na+10n→2411Na
The reaction above is an example of
Frage 26 Bericht
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Frage 27 Bericht
Reduction of nitroalkanes, nitrites and amides is a route for the preparation of
Frage 28 Bericht
0.05 mol dm-3 HCl is neutralized by 25 cm3 NaOH. If the volume of acid used is 32.00cm3, what is the concentration of the base
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HCl + NaOH → NaCl + H2O
CAVA = NA/NB = (0.05 * 32)/(CB * 25)
∴ CB = (0.05 * 32)/25 = 0.064 mol dm-3
Frage 29 Bericht
117.0g of sodium chloride was dissolved in the solubility in 1.0dm3 of distilled water at 25oC. Determine the solubility in mol dm-3 of sodium chloride at that temperature
[Na = 23, Cl = 35.5]
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Relative molecular mass of NaCl = 23 + 35.5 = 55.5 g/mol
No. of mole of NaCl = 117/55.5 = 2.1 mol
Frage 30 Bericht
When a solution of ammonium trioxocarbonate (IV) is added to a solution of an unknown salt, a white precipitate which is soluble in dilute hydrochloric acid but insoluble in ethanoic acid is formed. This indicates the presence of
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Frage 32 Bericht
Use the diagram to answer this question.
The gas that can be used to demonstrate the experiment is
Frage 34 Bericht
Insoluble salts can be prepared by
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Two soluble metal salts react with each other to form one soluble salt and one insoluble salt . Lead nitrate solution and sodium chloride solution react to produce solid lead chloride , leaving soluble sodium nitrate in solution. The lead chloride can be recovered by filtration.
Frage 35 Bericht
In the course of purifying water for town supply the water is passed through large settlings tanks, containing sodium aluminate (III) to remove
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Frage 37 Bericht
Diffusion is slowest in solid particles than in particles of liquid and gases because
Frage 39 Bericht
The rate of a reaction usually decrease in the concentration of reactants because
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Frage 40 Bericht
2Na(s) + 2H2O(l) → 2NaOH(aq) + H2(g)
From the equation above, calculate the mass of sodium hydroxide produced by 2.3g of sodium.
[H = 1, O = 16, Na = 23]
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2Na(s) + 2H2O(l) → 2NaOH(aq) + H2(g)
Relative molecular mass of NaOH = 23 + 16 + 1 = 40smol-1
2 * 23g of sodium react with water to produce
2 * 40g of NaOH
∴ 2.3g of sodium will react with water to produce
(2.3 * 40 * 2)/(23 * 2) = 4.00g
Frage 41 Bericht
Use the diagram to answer this question.
The colour of the fountain water is
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Frage 42 Bericht
In the periodic table, the electrical and thermal conductivities are properties of elements that
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Frage 43 Bericht
The experiment that showed that atoms have tiny positively charged nucleus was first carried out by
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Frage 44 Bericht
300 cm3 of gas has a pressure of 800 mmHg. If the pressure is reduced to 650 mmHg, find its volume
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P1V1= P2V2
800 * 300 = 650 * V2
V2 = (800 * 300)/650 = 369.23 cm3
Frage 45 Bericht
The uncovered raw food that is sold along major roads is likely to contain some amounts of
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Frage 46 Bericht
The atom of an element X is represented as yzX . The basic chemical properties of X depend on the value of
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Frage 47 Bericht
A hydrocarbon X with a molar mass of 26 consists of 92.3% carbon. What is its molecular formular
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% of H2 = 100 - 92.3 = 7.7%
mole = 92.3/12 7.7/1
7.1/7.1 7.1/7.1
empirical formula = CH
(CH)n = 26
(12 + 1)n = 26
(13)n = 26
n = 26/13 = 2
molecular formula = C2H2
Frage 49 Bericht
Detergents are manufactured with straight hydrocarbon chains so as to make them
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