JAMB UTME - Chemistry - 2008

The IUPAC nomenclature for the structure above is

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In recharging a lead-acid accumulator, the reaction at the cathode can be represented as

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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

Polyvinyl chloride is used in the production of

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The atom of an element X is represented as ${}_z^{y}X$. The basic chemical properties of X depend on the value of

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${}_{11}^{11}Na{+}_0^{1}n{\to }_{11}^{24}Na$

The reaction above is an example of

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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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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

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.

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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NH3(g) + HCl(s) → NH4Cl(s)

The entropy change in the system above is

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Choose the correct option from the structure above

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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

Use the diagram to answer this question.

The gas that can be used to demonstrate the experiment is

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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

The diagram above represent the electron sub-level for

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Leads is used for making bullets and lead shots because of its

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Reduction of nitroalkanes, nitrites and amides is a route for the preparation of

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Air boiled out of water as steam is richer in

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The uncovered raw food that is sold along major roads is likely to contain some amounts of

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The rate of a reaction usually decrease in the concentration of reactants because

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Reduction of alkanonoes with LialH4 produces

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The type of isomerism shown by cis- and trans- isomers is

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The vulcanizer's solution is prepared by dissolving rubber in

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In the periodic table, the electrical and thermal conductivities are properties of elements that

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Which of the following reaction is endothermic?

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A catalyst speeds up the rate of chemical reaction by

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The experiment that showed that atoms have tiny positively charged nucleus was first carried out by

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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

What is the IUPAC nomenclature of the compound NaCIO?

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Which of the following compounds of trioxonitrate (V) will decomposes to give dinitrogen (i) oxide and water when heated?

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The basicity of CH3COOH is

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Diffusion is slowest in solid particles than in particles of liquid and gases because

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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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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

If the silver mirror test is positive, it indicates the presence of an

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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

The product obtained when a mixture of benzene vapour and hydrogen are passed over nickel catalyst at 180oC is

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If glucose is heated with concentration tetraoxosulphate (VI) acid, it will be dehydrated to

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Detergents are manufactured with straight hydrocarbon chains so as to make them

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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

Use the diagram to answer this question.

The colour of the fountain water is

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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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When a few drops of water is added to a blue anhydrous cobalt (II) chloride, the colour changes to

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In countries where the temperature falls below 273K, salt is always sprinkled on the icy road in order to

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The most common ores of iron include

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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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