NECO SSCE - Chemistry - 2003 (Objective)

Wo Idahun

Ibeere 2 Ìròyìn

Which separation technique is routinely applied in the petroleum industry?

chromatography

distillation

evaporation

fractional crystallization

fractional distillation Ìdáhùn tó tọ́

Awọn alaye Idahun

Ka ìwé ẹ̀kọ́ nípa Separation Of Mixtures And Purification Of Chemical Substances (JAMB)

Separation Of Mixtures And Purification Of Chemical Substances

Wo Idahun

Ibeere 3 Ìròyìn

Which compound will give propane when it Is dehy drated by an excess of hot, concentrated tetraoxosvlphate(VI) acid?

CH₃CH₂CHO

CH₃CH₂CH2OH Ìdáhùn tó tọ́

CH₃CH₂COQH

CH₃CH₂0CH

CH₃CH₃OH

Awọn alaye Idahun

Wo Idahun

Ibeere 4 Ìròyìn

Which formula is used to indicate the degree of acidity of an acid?

\( [H^+] = ^{\text{mass of acid relative}} molecular mass of acid \)

F = number of H+ = ions x molar mass of the acid

Kw = [H+][OH-]

pH = - log₁₀[H+] Ìdáhùn tó tọ́

pKa = -log₁₀Ka

Awọn alaye Idahun

Ka ìwé ẹ̀kọ́ nípa Acids, Bases And Salts (Ghana Only) (WAEC)

Ka ìwé ẹ̀kọ́ nípa Periodic Chemistry (Ghana Only) (WAEC)

Periodic Chemistry (Ghana Only)

Wo Idahun

Ibeere 5 Ìròyìn

The pH of water is 7.

What is the pH of orange juice?

above 10

below 2

between 5.5 and 6.5 Ìdáhùn tó tọ́

between 7.5 and 8.5

Awọn alaye Idahun

Ka ìwé ẹ̀kọ́ nípa Acids, Bases And Salts (Ghana Only) (WAEC)

Wo Idahun

Ibeere 6 Ìròyìn

What is the number of moles of NaHCO₃in 250cm³ of its solution if the solution contains 8.4 g of NaHCO₃ in 1 dm³ of the solution. [Na = 23, 0 = 16, C = 12, H = 1)

0.25

0.05

0.025 Ìdáhùn tó tọ́

0.01

Awọn alaye Idahun

Ka ìwé ẹ̀kọ́ nípa Stoichiometry And Chemical Reactions (WAEC)

Stoichiometry And Chemical Reactions

Wo Idahun

Ibeere 7 Ìròyìn

What is formed when starch is completely hydrolysed?

fructose

glucose Ìdáhùn tó tọ́

lactose

maltose

sucrose

Awọn alaye Idahun

Ka ìwé ẹ̀kọ́ nípa Kinetic Theory Of Matter And Gas Laws (JAMB)

Ka ìwé ẹ̀kọ́ nípa Oxidation And Reduction (JAMB)

Ka ìwé ẹ̀kọ́ nípa Acids, Bases And Salts (Ghana Only) (WAEC)

Oxidation And Reduction

Wo Idahun

Ibeere 8 Ìròyìn

An atom of element X has an electronic configuration of \( 1s^22p^33s^23p^2. \) In which group of the periodic table is X?

\( \text{0} \)

4 Ìdáhùn tó tọ́

Awọn alaye Idahun

Ka ìwé ẹ̀kọ́ nípa Atomic Structure And Bonding (JAMB)

Wo Idahun

Ibeere 9 Ìròyìn

How many Faradays of electricity are required to liberate 9g of aluminium? [Al = 27]

0.1

0.3

1 Ìdáhùn tó tọ́

2.7

Awọn alaye Idahun

Ka ìwé ẹ̀kọ́ nípa Electrolysis (JAMB)

Electrolysis

Wo Idahun

Ibeere 10 Ìròyìn

Which metal bromide is widely used in photography?

calcium bromide

magnesium bromide

potassium bromide

silver bromide Ìdáhùn tó tọ́

sodium bromide

Awọn alaye Idahun

Ka ìwé ẹ̀kọ́ nípa Metals And Their Compounds (JAMB)

Metals And Their Compounds

Wo Idahun

Ibeere 11 Ìròyìn

Which is NOT a synthetic polymer?

nylon

Orion

Perspex

polystyrene

wool Ìdáhùn tó tọ́

Awọn alaye Idahun

Ka ìwé ẹ̀kọ́ nípa Basic Biochemistry And Synthetic Polymers (WAEC)

Basic Biochemistry And Synthetic Polymers

Wo Idahun

Ibeere 12 Ìròyìn

Which method is used for the purification of copper from its ore?

distillation

electrochemical

electrolysis Ìdáhùn tó tọ́

neutralization

reduction

Awọn alaye Idahun

Ka ìwé ẹ̀kọ́ nípa Electrolysis (JAMB)

Electrolysis

Wo Idahun

Ibeere 13 Ìròyìn

What change will occur to the equilibrium mixture
\( 2CrO^{2-}_4(aq) + 2H^+(aq) ⇔ Cr_2O^{2-}_7(aq) + H_2O(l) \) when excess sodium hydrogen solution is added?

A yellow precipitate of Cr(OH)₃ is formed

An orange precipitate of Cr(OH)₃ is formed

The colour changes from orange to yellow Ìdáhùn tó tọ́

The colour changes from yellow to orange

There is no visible reaction.

Awọn alaye Idahun

Ka ìwé ẹ̀kọ́ nípa Chemical Kinetics And Equilibrium Systems (Ghana Only) (WAEC)

Ka ìwé ẹ̀kọ́ nípa Structure Of The Atom (WAEC)

Chemical Kinetics And Equilibrium Systems (Ghana Only)

Structure Of The Atom

Wo Idahun

Ibeere 14 Ìròyìn

Ethene decolourises acidified potassium tetraoxomanganate(VII) solution. Which gas will decolourise bromine water?

CH₄

C₂H₆

C₃H₆ Ìdáhùn tó tọ́

C₃H₈

C₆H₆

Awọn alaye Idahun

Ka ìwé ẹ̀kọ́ nípa Chemistry Of Carbon Compounds (Ghana Only) (WAEC)

Chemistry Of Carbon Compounds (Ghana Only)

Wo Idahun

Ibeere 15 Ìròyìn

Which statement is NOT true about the composition of starch?

It contains only the atoms of carbon, hydrogen oxygen

It is a polysaccharide

Its empirical formula is C₂H₂0. Ìdáhùn tó tọ́

It is made from the monomerC₆H₁₂O₆.

The hydrogen and oxygen atoms are in the ratio 2:1.

Awọn alaye Idahun

Ka ìwé ẹ̀kọ́ nípa Chemistry Of Carbon Compounds (Nigeria Only) (WAEC)

Wo Idahun

Ibeere 16 Ìròyìn

Which element is the most electronegative?

calcium

fluorine Ìdáhùn tó tọ́

iodine

oxygen

sodium

Awọn alaye Idahun

Ka ìwé ẹ̀kọ́ nípa Atomic Structure And Bonding (JAMB)

Wo Idahun

Ibeere 17 Ìròyìn

Which hydrocarbon does NOT exhibit structural isomerism?

C₃H₆ Ìdáhùn tó tọ́

C₄H₆

C₄H₈

C₄H₁₀

C₅H₁₂

Awọn alaye Idahun

Ka ìwé ẹ̀kọ́ nípa Chemistry Of Carbon Compounds (Nigeria Only) (WAEC)

Wo Idahun

Ibeere 18 Ìròyìn

What is the IUPAC name of CH₃CCI=C(CH₃)2?

2-chloro -3 methylbut -2yne

2 -chloro -3 methylbut -2ene Ìdáhùn tó tọ́

2 -chloro -3 methylbutene

3- methyl -2-chlorobut -2-ene

3- methyl -2. chlorobut -2 yne

Awọn alaye Idahun

Ka ìwé ẹ̀kọ́ nípa Chemistry Of Carbon Compounds (Nigeria Only) (WAEC)

Wo Idahun

Ibeere 19 Ìròyìn

The reaction C₂H₆ → C₂H + H₂ is known as

dehydration

dehydrogenation Ìdáhùn tó tọ́

displacement

hydrogenation

reduction

Awọn alaye Idahun

Ka ìwé ẹ̀kọ́ nípa Chemistry Of Carbon Compounds (Nigeria Only) (WAEC)

Wo Idahun

Ibeere 20 Ìròyìn

Naturally occurring lithium consists of 90% \( ^7_3Li \text{ and 10% } ^6_3 Li. \) What is the relative atomic mass of lithium?

6.8

6.9 Ìdáhùn tó tọ́

7.1

Awọn alaye Idahun

Ka ìwé ẹ̀kọ́ nípa Kinetic Theory Of Matter And Gas Laws (JAMB)

Ka ìwé ẹ̀kọ́ nípa Atomic Structure And Bonding (JAMB)

Wo Idahun

Ibeere 21 Ìròyìn

Small amounts of compounds of transition metals are sometimes added to glass during manufacture in order to make the glass

acquire certain colours Ìdáhùn tó tọ́

easier to melt

easier to mould

little brittle

more transparent

Awọn alaye Idahun

Ka ìwé ẹ̀kọ́ nípa Chemical Combination (JAMB)

Chemical Combination

Wo Idahun

Ibeere 22 Ìròyìn

The number of hydrogen ions in 1.0dm6.00x10³ of a 0.25 mole dm6.00x10^-3 tetraoxosulphate(Vl) acid solution is
[Avogadro constant = 6.0 x 1 0]

1.45x10²³

1.50 x l0²³ Ìdáhùn tó tọ́

3.00x10²³

3.15x10²³

6.00x10²³

Awọn alaye Idahun

Ka ìwé ẹ̀kọ́ nípa Stoichiometry And Chemical Reactions (WAEC)

Stoichiometry And Chemical Reactions

Wo Idahun

Ibeere 23 Ìròyìn

Chlorine displaces bromine from aqueous potassium bromide because

bromine is a liquid at room temperature

bromine is weakly acidic.

bromine has a greater atomic radius than chlorine

chlorine is a stronger oxidising agent than bromine. Ìdáhùn tó tọ́

the density of chlorine is less than the density of bromine.

Awọn alaye Idahun

Ka ìwé ẹ̀kọ́ nípa Kinetic Theory Of Matter And Gas Laws (JAMB)

Ka ìwé ẹ̀kọ́ nípa Separation Of Mixtures And Purification Of Chemical Substances (JAMB)

Separation Of Mixtures And Purification Of Chemical Substances

Wo Idahun

Ibeere 24 Ìròyìn

At s.t.p, a mole of chlorine occupies 22.4dm³. If the temperature is changed to 35°C and the pressure to 750mHg the of the new volume will be [Cl = 35.5]

\( ^{\text{760 x 22.4 x 308}} \text{750 x 273x 35.5} dm^3 \)

\( ^{\text{760 x 22.4 x 308}} \text{750 x 273}^x dm^3 \) Ìdáhùn tó tọ́

\( ^{\text{750 x 22.4 x 35.5}} \text{760 x 273dm3} \)

\( ^{\text{760 x 22.4 x 35.5}} \text{750x22.3x273} \)

\( ^{\text{760 x 22.4 x 35.5}} \text{750 x 308dm3} \)

Awọn alaye Idahun

Ka ìwé ẹ̀kọ́ nípa Kinetic Theory Of Matter And Gas Laws (JAMB)

Wo Idahun

Ibeere 25 Ìròyìn

Which metal is a constituent of both bronze and solder?

copper

lead

silver

tin Ìdáhùn tó tọ́

zinc

Awọn alaye Idahun

Ka ìwé ẹ̀kọ́ nípa Metals And Their Compounds (JAMB)

Metals And Their Compounds

Wo Idahun

Ibeere 26 Ìròyìn

In the reaction 2H₂S(g) + SO₂(g) → 2H₂SO(I)+3S(s)SO₂is acting as _agent

a bleaching

a dehydrating

an oxidizing Ìdáhùn tó tọ́

a precipitating

a reducing

Awọn alaye Idahun

Ka ìwé ẹ̀kọ́ nípa Kinetic Theory Of Matter And Gas Laws (JAMB)

Ka ìwé ẹ̀kọ́ nípa Oxidation And Reduction (JAMB)

Oxidation And Reduction

Wo Idahun

Ibeere 27 Ìròyìn

What mass of copper is deposited when 6.5g of granulated zinc reacts with excess copper(II) tetraoxosulphate(VI) solution?

The equation for the reaction is: Zn(s) + \( CuSO_4(aq)→ ZnSO_4(aq)+ Cu(s)\)[CU= 64; Zn=65]

3.2 g

3.25 g

6.4 g Ìdáhùn tó tọ́

6.5 g

64.0 g

Awọn alaye Idahun

Ka ìwé ẹ̀kọ́ nípa Stoichiometry And Chemical Reactions (WAEC)

Stoichiometry And Chemical Reactions

Wo Idahun

Ibeere 28 Ìròyìn

Which metal is extracted from bauxite?

aluminium Ìdáhùn tó tọ́

calcium

copper

magnesium

tin

Awọn alaye Idahun

Ka ìwé ẹ̀kọ́ nípa Metals And Their Compounds (JAMB)

Metals And Their Compounds

Wo Idahun

Ibeere 29 Ìròyìn

Why is tetraoxosulphate(VI) acid NOT used for making carbon dioxide from calcium carbonate? It is

a dehydrating agent

a strong acid

an oxidising agent

dibasic

forms insoluble calcium tetraoxosulphate(Vl) Ìdáhùn tó tọ́

Awọn alaye Idahun

Ka ìwé ẹ̀kọ́ nípa Acids, Bases And Salts (JAMB)

Acids, Bases And Salts

Wo Idahun

Ibeere 30 Ìròyìn

Chlorine is used in water purification because it

bleaches impurities in the water

decolorizes water

destroys bacteria Ìdáhùn tó tọ́

is extremely soluble in water

is pleasant tasting

Awọn alaye Idahun

Ka ìwé ẹ̀kọ́ nípa Water (JAMB)

Water

Wo Idahun

Ibeere 31 Ìròyìn

Why does the treatment of cotton fabrics with dilute acids weaken the materials?

Cotton is hydrolysed completely to glucose

The fabrics are soluble in dilute acids

The molecular chains are partially broken Ìdáhùn tó tọ́

The molecular chain length f the fabric increases

The thread holding the fabric together Is completely destroyed.

Awọn alaye Idahun

Ka ìwé ẹ̀kọ́ nípa Acids, Bases And Salts (JAMB)

Ka ìwé ẹ̀kọ́ nípa Oxidation And Reduction (JAMB)

Acids, Bases And Salts

Oxidation And Reduction

Wo Idahun

Ibeere 32 Ìròyìn

A calcium atom and a calcium ion have the same

chemical properties

electric charge

electronic structure

number of electrons

number of neutrons Ìdáhùn tó tọ́

Awọn alaye Idahun

Ka ìwé ẹ̀kọ́ nípa Atomic Structure And Bonding (JAMB)

Wo Idahun

Ibeere 33 Ìròyìn

What is the change in the oxidation number of phosphorus in the following reaction?

4P(s) + 5O₂(ag) → 2P₂O₅(s)

0 to 2

0 to 5 Ìdáhùn tó tọ́

4 to 2

4 to 5

4 to 10

Awọn alaye Idahun

Ka ìwé ẹ̀kọ́ nípa Oxidation And Reduction (JAMB)

Oxidation And Reduction

Wo Idahun

Ibeere 34 Ìròyìn

The boiling point of water is higher than the boiling point of ethanol because

the bonding in water is electrovalent (ionic) whereas the bonding in ethanol is convalent

the hydrogen bonding between water molecules is stronger than the hydrogen bonding between ethanol molecules Ìdáhùn tó tọ́

water has a higher lattice energy than ethanol.

water has hydrogen bonding between its molecules but ethanol has no hydrogen bonging between its molecules;

water is a better solvent than ethanol.

Awọn alaye Idahun

Ka ìwé ẹ̀kọ́ nípa Chemical Bonds (Nigeria Only) (WAEC)

Ka ìwé ẹ̀kọ́ nípa Energy And Energy Changes (WAEC)

Chemical Bonds (Nigeria Only)

Energy And Energy Changes

Wo Idahun

Ibeere 35 Ìròyìn

What mass of silver is deposited when a current of 2.6 A is passed through a solution of a silver salt for 40 minutes? [Ag= 108 ; F=96500C]

6.89g

6.93g

6.98g Ìdáhùn tó tọ́

7.04g

7.12g

Awọn alaye Idahun

Ka ìwé ẹ̀kọ́ nípa Chemical Kinetics And Equilibrium System (Nigeria Only) (WAEC)

Ka ìwé ẹ̀kọ́ nípa Electrolysis (JAMB)

Chemical Kinetics And Equilibrium System (Nigeria Only)

Electrolysis

Wo Idahun

Ibeere 36 Ìròyìn

B is an isotope of the element \(^{238} _{92}Ur\). The isotope B has

46 protons and 119 neutrons

92 protons and 92 neutrons

92 protons and 146 neutrons Ìdáhùn tó tọ́

92 protons and 238 neutrons

Awọn alaye Idahun

Ka ìwé ẹ̀kọ́ nípa Atomic Structure And Bonding (JAMB)

Ka ìwé ẹ̀kọ́ nípa Chemical Equilibria (JAMB)

Chemical Equilibria

Wo Idahun

Ibeere 37 Ìròyìn

What change will occur during the electrolysis of brine using carbon electrodes?

Chlorine will be given off at the cathode Ìdáhùn tó tọ́

Oxygen gas will be given off at the anode

Sodium will be deposited at the cathode

The resulting solution, after electrolysis, will be acidic.

The volumes of hydrogen and chlorine given off during the same time are equal

Awọn alaye Idahun

Ka ìwé ẹ̀kọ́ nípa Electrolysis (JAMB)

Ka ìwé ẹ̀kọ́ nípa Acids, Bases And Salts (Ghana Only) (WAEC)

Electrolysis