JAMB UTME - Chemistry - 1984

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Question 11 Report

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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Question 12 Report

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 13 Report

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

isopropylethene

acetylene

3- methylbutane

2-methylbutane

5-methylpentane

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Question 14 Report

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 15 Report

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 16 Report

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 17 Report

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 18 Report

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

Answer Details

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 19 Report

Sodium chloride may be obtained from brine by

titration

decantation

distillation

evaporation

sublimation

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Question 20 Report

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 21 Report

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 22 Report

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 23 Report

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 24 Report

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 25 Report

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 26 Report

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 27 Report

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 28 Report

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 29 Report

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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Question 30 Report

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 31 Report

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 32 Report

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 33 Report

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 34 Report

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 Report

The hybridization of the carbon atom in ethyne is

sp 4

sp 3

sp2

sp

s