JAMB UTME - Chemistry - 1984

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Pregunta 2 Informe

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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Pregunta 3 Informe

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

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Pregunta 4 Informe

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

isopropylethene

acetylene

3- methylbutane

2-methylbutane

5-methylpentane

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Pregunta 5 Informe

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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Pregunta 6 Informe

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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Pregunta 7 Informe

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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Pregunta 8 Informe

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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Pregunta 9 Informe

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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Pregunta 10 Informe

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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Pregunta 11 Informe

Sodium hydroxide (NaOH) pellets are

deliquescent

hygroscopic

efflorescent

hydrated

fluorescent

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Pregunta 12 Informe

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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Pregunta 13 Informe

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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Pregunta 14 Informe

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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Pregunta 15 Informe

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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Pregunta 16 Informe

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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Pregunta 17 Informe

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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Pregunta 18 Informe

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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Pregunta 19 Informe

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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Pregunta 20 Informe

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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Pregunta 21 Informe

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

Detalles de la respuesta

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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Pregunta 22 Informe

The hybridization of the carbon atom in ethyne is

sp 4

sp 3

sp2

sp

s

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Pregunta 23 Informe

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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Pregunta 24 Informe

An example of a neutral oxide is

AL2O3

NO2

CO2

CO

SO2

Acids, Bases And Salts

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Pregunta 25 Informe

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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Pregunta 26 Informe

For the reaction 2Fe3+ 2I- $\to$ 2Fe2+ + I2, which of the following statements is TRUE?

Fe is oxidized to Fe3+

Fe3+ is oxidized to Fe2+

I- is oxidized to I2

I- is reduced to I2

I- is displacing an electron from Fe3+

Electrolysis

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Pregunta 27 Informe

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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Pregunta 28 Informe

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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Pregunta 29 Informe

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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Pregunta 30 Informe

The name of the compound above is

acetic acid

propanal

propanol

ethanoic acid

propanoic acid

Acids, Bases And Salts

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Pregunta 31 Informe

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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Pregunta 32 Informe

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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Pregunta 33 Informe

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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Pregunta 34 Informe

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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Pregunta 35 Informe

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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Pregunta 36 Informe

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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Pregunta 37 Informe

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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Pregunta 38 Informe

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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Pregunta 39 Informe

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