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Chemistry Past Questions

Study and practice Chemistry past questions with answers and detailed explanations. Then test your knowledge using our interactive CBT practice platform and prepare confidently for your upcoming examinations.

92 questions JAMB 2505 WAEC 1623 NECO 168 CUSTOM 10

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Question 41

jamb 2004

Chlorine consisting of two isotopes of mass number 35 and 37 in the ratio 3:1 has an atomic mass of 35.5. Calculate the relative abundance of the isotopes of mass number 37

A20

B25

C60

D75

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Question 42

jamb 2004

The property of chlorine which causes hydrogen chloride to be more ionic than the chlorine molecules is its

Aelectrovalency

Belectron affinity

Celectropositivity

Delectronegativity

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Question 43

jamb 2004

\(^{226}\)\(_{88}\)Ra → \(^x\)\(_{86}\)Rn + α - particle
What is the value of x in the nuclear reaction above?

A220

B222

C226

D227

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Question 44

jamb 2004

The shape of s-orbitals is

Aspherical

Belliptical

Cspiral

Dcircular

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Question 45

jamb 2004

An electron can be added to a halogen atom to form a halide ion with

A2 valence electrons

B3 valence electrons

C7 valence electrons

D8 valence electrons

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Question 46

jamb 2004

A given volume of methane diffuses in 20s. How long will it take the same volume of sulphur (IV) oxide to diffuse under the same conditions?
[C = 12, H = 1, S = 32, O = 16

A5s

B20s

C40s

D60s

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Question 47

jamb 2004

It is difficult to achieve an orderly arrangement of the molecules of a gas because they?

Ahave no definite shape

Bhave little force of attraction between them

Ccan collide with one another in the container

Dare too small in size

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Question 48

jamb 2004

According to charles' law, the volume of a gas becomes zero at

A0 ^oC

B-100 ^oC

C-273 ^oC

D-373 ^oC

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Question 49

jamb 2004

What volume of gas is evolved at S.t.p if 2g of calcium trioxocarbonate (IV) is added to a solution of hydrochloric acid?
[Ca = 40, C = 12, O = 16, Cl = 35.5, H = 1 Molar volume of a gas at s.t.p = 22.4 dm\(^3\)

A112 cm³

B224 cm³

C448 cm³

D2240 cm³

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Question 50

jamb 2004

If a solution contains 4.9g of tetraoxosulphate (VI) acid, calculate the amount of copper (II) oxide that will react with it
[Cu = 64, O = 16, S = 32, H = 1]

A0.8g

B4.0g

C40.0g

D80.0g

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Question 51

jamb 2004

A chemical reaction is always associated with

Aan increase in the composition of one of the substance

Ba change in the volume of the reactants

Ca change in the nature of the reactants

Dthe formation of new substance

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Question 52

jamb 2004

When a solid substance disappears completely as a gas on heating, the substance is said to have undergone

Aevaporation

Bdistillation

Ccrystallization

Dsublimation

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