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Chemistry Past Questions

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4,306 questions JAMB 2505 WAEC 1623 NECO 168 CUSTOM 10

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4,306 questions

Question 1 of 20 4,306 total questions

Question 1851

waec 1989

The most suitable method to use when separating an insoluble solid from a liquid is

Aevaporation

Bfiltration

Cmagnetization

Dsublimation

Edistillation

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Question 1852

waec 1989

Which of the following hydrocarbons is not likely to be present in petrol?

AC₁₄H₃₀

BC₁₀H₂₂

CC₉H₂₀

DC₇H₁₆

EC₅H₁₂

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Question 1853

waec 1989

The earthly impurities in iron ore are removed in the blast furnace by the reaction

ACO₂ + C →2CO

BFe₂O₃ + 3CO →2Fe + 3CO₂

CSiO₂ + CaO →CaSiO₃

DCaCO₃ → CaO + CO₂

EC +CO₂ → CO₂

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Question 1854

waec 1989

120cm\(^3\) of hydrogen were sparked with 60cm\(^3\) of oxygen at 110\(^o\)C. What was the volume of steam produced? The equation for the reaction is

2H\(_2\)(\(_g\) + O\(_2\)(\(_g\) → 2H\(_2\)O\(_g\)

A30cm³

B60cm³

C90cm³

D120cm³

E180cm³

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Question 1855

waec 1989

Which of the following statements best explains cracking ? It is a process

Ain which an alkene adds on itself repeatedly to form long chain polymers

Bin which large hydrocarbon molecules are broken into smaller units

Cfor measuring theoctane number of petrol

Din which carbon chain results in a zigzag arrangement

Ein which aromatic hydrocarbons are produced

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Question 1856

waec 1989

Which of the following reactions represents the laboratory preparation of hydrogen?

AC_(s) + H₂O_(l) → CO_(g) + H_2(g)

B2Na_(s) + 2H₂O_(l) → 2NaOH_(aq) + H_2(g)

CZn_{(s) + 2HCI_(aq) → ZnCI_2(aq) + H_2(g)}

DCu_(s) + H₂O_(l) → CuO_(s) + H_2(g)

E2AI_(s) + 3H₂O_{(l) → Al₂O_3(s) + 3H_2(g)}

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Question 1857

waec 1989

The major raw material in a plastic industry is

Aethanol

Bsulphur

Cmethylethanoate

Dethene

Eethane

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Question 1858

jamb 1989

CO(g) + H\(_2\)O(g) \(\to\) \(CO_{2g}\) + H\(_2\)(g) \(\Delta\)H = - 4100J. Which of the following factors favour the formation of hydrogen in the above reaction? i. high pressure. ii. low pressure iii. high-temperature iv. use of excess steam

Ai, iii and iv

Biii only

Cii, iii and i

Div only

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Question 1859

jamb 1989

What is the IUPAC name for the compound

A1-chloro-2-methylprop-2,3-ene

B1-chloro-2-methylprop-2-ene

C3-chloro-2-methylprop-1-ene

D3-chloro-2methylprop-1,2-ene

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Question 1860

jamb 1989

Use the figure above to answer this question. Which of the following is NOT an isomer of the compound?

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Question 1861

jamb 1989

Use the figure above to answer this question. Which of the following compounds is an isomer of the compound

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Question 1862

jamb 1989

The above graph shows a typical heating curve from the solid phase through the liquid phase to the gaseous phase of a substance. Which part of the curve shows solid and liquid in equilibrium?

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Question 1863

jamb 1989

If in the graph above 1 dm 3 of a saturated solution of KCL is cooled from 80°C, the mass of crystals deposited will be
[K = 39, Cl = 35.5]

A7.45 g

B14.90 g

C74.50 g

D149.00 g

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Question 1864

jamb 1989

The above diagram gives the potential energy profile of the catalyst and uncatalysed reactions of X(g) + Y(g) → XY(g). Deduce the respective activation energies in KJ of the catalysed and uncatalysed reverse reactions: XY(g) → X(g) + Y(g)

A300, 500

B500, 300

C-300, -500

D-500, -300

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Question 1865

jamb 1989

Which of the curves in the above graph illustrates the behaviour of an ideal gas?

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Question 1866

jamb 1989

In the above set up substances X and Y are respectively

Alime water copper (ll) tetraoxosulphate (lV)

Bpotassium trioxocarbonate and alkaline pyrogallol

Cpotassium hydroxide and alkaline pyrogallol

Dpotassium trioxocarbonate (lV) and concentrated tetraoxosulphate (IV) acid

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Question 1867

jamb 1989

It can be deduced from the vapour pressure curves above that

Aliqiud 1 has the highest boiling point

Bliquid ll has the highest boiling point

Cliquid lll has the highest boiling point

Dliquid lll has the lowest boiling point

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Question 1868

jamb 1989

Three liquids X, Y and Z containing only hydrogen and carbon were burnt on a spoon. X and Y burnt with sooty flames while Z did not. Y is able to discharge the colour of bromine water whereas X and Z cannot. Which of the liquids would be aromatic in nature?

AX and Z

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Question 1869

jamb 1989

The gas responsible for most of the fatal explosions in coal mines is

Abutane

Bethene

Cethane

Dmethane

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Question 1870

jamb 1989

The alkaline hydrolysis of fats and oils produces soap and

Apropane 1, 1, 3 - triol

Bpropane - 1,2,3 - triol

Cpropane - 1,3,3 - triol

Dpropane - 1, 2, 2 - triol

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