JAMB UTME - Chemistry - 1984

Electrolysis

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Question 2 Rapport

An organic compound with a vapour density 56.5 has the following percentage composition:C =53.1% N = 12.4%, O = 28.3%, H = 6.2%. The molecular formula of the compound is

Relative atomic masses: N = 14, O = 16, C = 12, H = 1 )

C3H6O2N

C5H6O2N

(C5H7O2N)1/2

C5H7O2N

(C5H7O2N)2

Chemistry Of Carbon Compounds (Ghana Only)

Solubility Of Subtances (Nigeria Only)

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Question 3 Rapport

Alkaline hydrolysis of naturally occurring fats and oils yields

fats and acids

soaps and glycerol

margarine and butter

esters

detergents

Acids, Bases And Salts

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Question 4 Rapport

Which of the following methods may be used to prepare trioxonitrate (V) acid (nitric acid) in the laboratory?

Heating ammonia gas with tetraoxosulphate (VI) acid

Heating ammonium trioxonitrate (V) with tetraoxosulphate (VI) acid

Heating sodium trioxonitrate (V) with tetraoxosulphate (VI) acid

Heating potassium trioxonitrate (V) with calcium hydroxide

Heating a mixture of ammonia gas and oxygen.

Periodic Chemistry (Ghana Only)

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Question 5 Rapport

Use the diagram above to answer this question.

Which of the following structural formula is NOT isomeric with the others?

A

B

C

D

E

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Question 6 Rapport

The diagram above (Fig.3) shows the energy profile for the reaction A + B + = C + D From this diagram, it is clear that the reaction is

spontaneous

isothermal

adiabatic

exothermic

endothermic

Energy Changes

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Question 7 Rapport

At S. T. P how many litres of hydrogen can be obtained from the reaction of 500 cm3 of 0.5 M H 2SO 4 with excess zinc metal?

(Gram molecular volume of H2 = 22. 4 dm 3)

22.4 dm 3

11 . 2 dm 3

6. 5 dm 3

5. 6 dm 3

0. 00 dm 3

Stoichiometry And Chemical Reactions

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Question 8 Rapport

Which of the curves shown in the figure given represents the relationships between the volume(V) and pressure(P) of an ideal gas at constant temperature?

1

2

3

4

1 and 3

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Question 9 Rapport

From the reactions : ZnO + Na2O $\to$ NaZnO and ZnO + CO2 $\to$ ZnCO3 it may be concluded that zinc oxide is

neutral

basic

acidic

amphoteric

a mixture

Chemistry Of Carbon Compounds (Ghana Only)

Chemical Combination

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Question 10 Rapport

The balanced equation for the reaction of tetraoxosulphate(VI)acid with aluminium hydroxide to give water and aluminium tetraoxosulphate(VI) is

H2SO4 + Al(OH)2

\to

2H2O + AlSO4

3H2SO4 + 2Al(OH)3

\to

6H2O + Al2(SO4)3

3H2SO4 + 2AlH

\to

6H2O + Al(SO4)3

H2 SO4 + 2Al(OH)3

\to

Al(SO4)3

H2SO4 + Al(OH)3

\to

H2O + Al2(SO4)3

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Question 11 Rapport

An example of a neutral oxide is

AL2O3

NO2

CO2

CO

SO2

Acids, Bases And Salts

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Question 12 Rapport

3Cl2 + 2NH3 $\to$ N2 + 6HCl. In the above reaction, ammonia acts as

a reducing agent

an oxidizing agent

an acid

a catalyst

a dry agent

Oxidation And Reduction

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Question 13 Rapport

An element that can exist in two or more different structural forms which possess the same chemical properties is said to exhibit.

polymerism

isotopy

isomorphism

isomerism

allotrophy

Structure Of The Atom

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Question 14 Rapport

In which of the following reactions does hydrogen peroxide act as a reducing agent?

H2S + H2O2

\to

S + 2H2O

PbSO3 + H2O2

\to

PbSO4 + H2O

2I+ 2H+ + H2O2

\to

I2 + 2H2O

PbO2 + 2HNO3 + H2O2

\to

Pb(NO3)2 + 2H2O + O2

SO2 + H2O2

\to

H2SO4

Oxidation And Reduction

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Question 15 Rapport

Water is said to be 'hard' if it

easily forms ice

has to be warmed before sodium chloride dissolves in it

froms an insoluble scum with soap

contains nitrates

contains sodium ions

Water

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Question 16 Rapport

Which of the following electrodes is used in electrolysis of bauxite (Al2O3) in molten cryolite?

Steel electrodes

Carbon electrodes

Mercury electrodes

Carbon anode and steel cathode

Carbon cathode and stell anode

Electrolysis

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Question 17 Rapport

Which of the following statements is NOT true of carbon monoxide?

CO is poisonous

CO is readily oxidized at room temperature by air to form CO2

CO may be prepared by reducing CO2 mixed with coke heated to about 1000oC

CO may be prepared by heating charcoal with a limited amount of O2

CO is a good reducing agent

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Question 18 Rapport

Sodium chloride may be obtained from brine by

titration

decantation

distillation

evaporation

sublimation

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Question 19 Rapport

A piece of sea shell, when dropped into a dilute solution of hydrochloric acid, produces a colourless, odourless gas which turns clear limewater milky. The sea shell contains

sodium chloride

ammonium nitrate

calcium carbonate

calcium chloride

magnesium chloride

Acids, Bases And Salts

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Question 20 Rapport

When the kerosene fraction from petrol is heated at high temperature, a lower boiling liquid is obtained. This process is known as

polymerization

refining

hydrogenation

cracking

Solubility

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Question 21 Rapport

Use the diagram above to answer this question.

Which of the following represents a carboxylic acid?

A

B

C

D

E

Periodic Chemistry (Ghana Only)

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Question 22 Rapport

The name of the compound above is

acetic acid

propanal

propanol

ethanoic acid

propanoic acid

Acids, Bases And Salts

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Question 23 Rapport

If an excess of a liquid hydrocarbon is poured into a jar of chlorine, and the sealed jar is then exposed for several hours to bring sunlight, all the chlorine gas is consumed. The hydrocarbon is said to have undergone

a polymerization reaction

an isomerization reaction

an addition reaction

a substitution reaction

a reduction reaction

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Question 24 Rapport

Which among the elements 1. Carbon 2. Oxygen 3. Copper 4. Bromine 5. Zinc, will NOT react with either water or steam?

1 and 2

2 and 3

3 and 4

1, 2, and 3

2, 3, and 5

Non-metals And Their Compounds

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Question 25 Rapport

Alkanes

are all gases

have the general formula CnH2n + 2O

contain only carbon and hydrogen

are usually soluble in water

are usually active compounds

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Question 26 Rapport

In dilute solution the heat of the reaction NaOH + HCl = NaCl + H2O is - 57.3kJ. Therefore the heat of the reaction 2NaOH + H2SO4 $\to$ Na2SO4 + 2H2O is

+ 28.65 kJ

- 28.65KJ

+ 57.3KJ

- 114.6 KJ

- 229.2 KJ

Détails de la réponse

NaOH + HCl = NaCl + H2O $Δ$ H = -57.3kJ

Heat of reaction of 2NaOH + H2O4

NaSO4 + H2O is

= 57.3 x 2 = -114.6 kJ

Read lesson note on Kinetic Theory Of Matter And Gas Laws (JAMB)

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Question 27 Rapport

Sodium hydroxide (NaOH) pellets are

deliquescent

hygroscopic

efflorescent

hydrated

fluorescent

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Question 28 Rapport

The ratio of the number of molecules in 2g of hydrogen to that in 16g of oxygen is

2:1

1:1

1:2

1:4

1:8

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Question 29 Rapport

The solubility curves of four substances are shown in the figure above. Which of the four substances would crystallize from a saturated solution cooled from 353K(80oC)to 323K(50C)?

P and Q

P and R

P and S

R and S

Q and R

Solubility

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Question 30 Rapport

The hybridization of the carbon atom in ethyne is

sp 4

sp 3

sp2

sp

s

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Question 31 Rapport

A molar solution of caustic soda is prepared by dissolving

40 g NaOH in 100 g of water

40 g NaOH in 1000 g of water

20 g NaOH in 500 of solution

20 g NaOH in 1000 g of solution

2o g NaOH in 80 g of solution

Acids, Bases And Salts

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Question 32 Rapport

If the cost of electricity required to deposit 1 g of magnesium is ₦5.00, how much would it cost to deposit 10g of aluminium?

₦10.00

₦27.00

₦44.44

₦66.67

₦33.33

Stoichiometry And Chemical Reactions

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Question 33 Rapport

Nitrogen can best be obtained from a mixture over oxygen and nitrogen by passing the mixture over

potassium hydroxide

heated gold

heated magnesium

heated phosphorus

calcium chloride

Chemical Combination

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Question 34 Rapport

Lime - water, which is used in the laboratory for the detection of carbon(iv)oxide is an aqueous solution of

Ca(OH)2

CaCO3

CaHCO3

CaSO4

N2CO3

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Question 35 Rapport

Sulphur

forms two alkaline oxides

is spontaneously flammable

burns with a blue flame

conducts electricity in the molten state

is usually stored in the form of sicks in water

Non-metals And Their Compounds

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Question 36 Rapport

Naphthalene when heated melts at 354 K (81 oC). At this temperature the molecules of naphthalene

decompose into smaller molecules

change their shape

are oxidized by atmospheric oxygen

contract

become mobile as the inter molecular forces are broken

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Question 37 Rapport

Which of the following statements is NOT correct about all four of the acids: HBr, HNO3, H 2CO3 and H2SO4? They

dissolve marble to liberate CO

have a PH less than 7

Turn blue litmus red

neutralize alkalis to form salt

react with magnesium to liberate hydrogen

Acids, Bases And Salts

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Question 38 Rapport

In the Haber process for the manufacture of ammonia, finely divided iron is used as

an ionizing agent

a reducing agent

a catalyst

a dehydrating agent

an oxidizing agent

Chemistry Of Carbon Compounds (Ghana Only)

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Question 39 Rapport

For the reaction NH4NO2 $\to$ N2 + 2H2O, calculate the volume of nitrogen that would be produced at S. T. P from 320 g of the dioxonitrate(iii)salt. (Relative atomic masses: N = 14, O = 16, H = 1)

2.24 dm 3

2.24 cm3

1. 123

1. 12dm 3

4. 48 dm 3

Stoichiometry And Chemical Reactions

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Question 40 Rapport

Which of the following statements is INCORRECT?

Fractional distillation of crude petroleum will give the folloing hydrocarbon fuels in order of increasing boiling point

Butane < petrol < kerosene of polythene.

Both but-1-ene and but-1-yne will decolorize bromine readily

but-2-ene will react with chlorine to form 2,3-dichlorobutane

calcuim carbide will react with water to form any alkyne

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Question 41 Rapport

Which of the following mixtures would result in a solution of pH greater than 7?

25.00 cm3 of 0.05 M H2SO4 and 25.00cm3 of 0.50 M Na2CO3

25.00 cm3 of 0.05 M H2SO4 and 25.00 cm3 of 0.10 M NaHCO3

25.00 cm3 of 0.11 MH2SO4 and 25.00cm3 0. 10 M NaOH

25.00cm3 of 0.11 MH2 SO4 and 50.00 cm3 of 0.05 M NaOH

25.00cm3 of 0.25 M H2SO4 and 50.00cm3 of 0.20 M NaOH

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Question 42 Rapport

The function of conc. H2SO4 in the esterification of ethanoic acid with ethanol is to

serve as a dehydrating agent

serve as a solvent

act as a catalyst

prevent any side reaction

serve as an oxidizing agent

Acids, Bases And Salts

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Question 43 Rapport

An aqueous solution of a metal salt, M, gives a white precipitate with NaOH which dissolves in excess NaOH. With aqueous ammonia, the solution of M also gives a white precipitate which dissolves in excess ammonia. Therefore cartion in M is

Zn ++

Ca++

Ai+++

Pb++

Cu++

Acids, Bases And Salts

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Question 44 Rapport

The I.U.P.A.C name for the compound is

isopropylethene

acetylene

3- methylbutane

2-methylbutane

5-methylpentane

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Question 45 Rapport

20 cm 3 of hydrogen gas are sparked with 20cm 3 of oxygen gas in an endimoeter at 373k (100 oC) and 1 atmosphere. The resulting mixture is cooled to 298 K (25 oC) and passed over calcium chloride. The volume of the residual gas is

40 cm 3

20 cm 3

30 cm 3

10cm 3

5cm 3