JAMB UTME - Chemistry - 2008

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

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

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

Which of the following reaction is endothermic?

300 cm3 of gas has a pressure of 800 mmHg. If the pressure is reduced to 650 mmHg, find its volume

Answer Details

P1V1= P2V2
800 * 300 = 650 * V2
V2 = (800 * 300)/650 = 369.23 cm3

Reduction of alkanonoes with LialH4 produces

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

In the course of purifying water for town supply the water is passed through large settlings tanks, containing sodium aluminate (III) to remove

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

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

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

The reaction above is an example of

NH3(g) + HCl(s) → NH4Cl(s)

The entropy change in the system above is

Use the diagram to answer this question.

The gas that can be used to demonstrate the experiment is

Air boiled out of water as steam is richer in

A catalyst speeds up the rate of chemical reaction by

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

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

Answer Details

HCl + NaOH → NaCl + H2O
CAVA = NA/NB = (0.05 * 32)/(CB * 25)
∴ CB = (0.05 * 32)/25 = 0.064 mol dm-3

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

A hydrocarbon X with a molar mass of 26 consists of 92.3% carbon. What is its molecular formular

Answer Details

% 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

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

The vulcanizer's solution is prepared by dissolving rubber in

What is the IUPAC nomenclature of the compound NaCIO?

The most common ores of iron include

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

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

Answer Details

The correct answer is 11.
pH = -log(H+) Or 14 - pOH
pOH = -log(0.001)
pOH = 3
pH = 14 - 3 = 11

The substance that is used in the steel industry for the removal of carbon, sulphur and phosphorus impurities from pig iron is

Choose the correct option from the structure above

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

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]

Answer Details

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

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

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]

Answer Details

Relative molecular mass of NaCl = 23 + 35.5 = 55.5 g/mol
No. of mole of NaCl = 117/55.5 = 2.1 mol

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

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

Polyvinyl chloride is used in the production of

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]

The oxidation state of carbon in HCOOH is

Answer Details

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

Insoluble salts can be prepared by

Answer Details

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.

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

Use the diagram to answer this question.

The colour of the fountain water is

The diagram above represent the electron sub-level for

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]

Answer Details

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

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

Chlorophyll obtained from given leaves of plant can be shown to be composed of more than one coloured component by the technique of

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

The IUPAC nomenclature for the structure above is

The basicity of CH3COOH is