Chapter 2: The Structure of the Atom

Paper 1

1) The diagram below shows a change in the state of matter.

Which of the following is process P? A Melting C SublimationB Condensation D Freezing

2) The diagram below shows the graph of the cooling of acetamide from its gaseous state to its solid state.

What is the boiling point and the time when liquid acetamide starts to condense? Boiling point Time condensation begins

A T1 m1

B T1 m3

C T2 m2 D T2 m4

3) The diagram below shows the graph of temperature against time for the heating of naphthalene.

What is the process of change in the state of matter, which occurs at temperature T oC, and the state of the substance at time t?

Process at temperature T State of the substance at time tA Melting Solid and liquidB Freezing Solid and liquid C Condensation Liquid and gasD Boiling Liquid and gas

4) Which of the following substances will undergo sublimation when heated?A Bromine C Ammonium chlorideB Sodium nitrate D Carbon

5) The diagram below shows an atomic model.

Which of the following scientists introduced this atomic model? A Earnest Rutherford C Sir Joseph John ThomsonB Niels Bohr D John Dalton

6) The diagram below shows the symbol of the potassium atom.

Which of the following is true about the symbol? Proton number Nucleon number Number of neutrons

A 19 19 39B 19 39 19C 19 39 20D 39 20 19

7) Which of the following is the maximum number of electrons in the shells of an atom?Shell Maximum number of electrons

A 1 1B 2 8C 3 18D 4 2

8) The diagram below shows the symbol of the sodium atom.

39

K19

23

Na11

What is the electron arrangement and the valence electrons of the sodium element?Electron arrangement Valence electron

A 2.1 3B 2.1 5C 2.8.1 1D 2.8.8.5 1

9) The diagram below shows the structure of atom X.

Which of the following statements are true?I Atom X has 6 protons II Atom X has 4 valence electronsIII The electron arrangement of atom X is 2.4IV The nucleon number of atom X is 6

A I and II only C I, III and IV onlyB I, II and III only D II, III and IV only

10) The following information is about the subatomic particles of atom Y.

Which of the following diagrams represents atom Y?A C

B D

Electron arrangement: 2.4Number of protons: 6Number of neutrons: 6

11) Element J has an electron arrangement of 2.8.3. If the nucleus of atom J has 14 neutrons, what are the proton number and the nucleon number of element J?

Proton number Nucleon numberA 13 14B 13 27C 14 27D 27 13

12) Which of the following isotopes is used to kill cancer cells?A Sodium-24 B Carbon-14 C Cobalt-60D Chlorine-35

13) Atom P has 9 protons and 10 neutrons. Which of the following is true about atom P?A Atom P has 10 electrons B Atom P has 8 valence electrons C Atom P has 2 shells filled with electronsD Atom P has a proton number of 19

14) Study atom X and atom Y in the diagram below.

Which of the following statements is true about atom X and Y?A They are different atomsB They are a pair of isotopes C They have five valence electrons D They are located in different groups of the Periodic Table

15)

Which of the following scientists gave the above explanation about an atom? A John Dalton B Sir James Chadwick C Ernest RutherfordD Sir Joseph John Thomson

79

X35

81

Y35

An atom is indivisible, cannot be produced or destroyed.

Paper 2Structured question

The table below shows four substances with their respective chemical formula.

Substance Chemical formulaIodine I2

Potassium chloride KClNaphthalene C10H8

Magnesium Mg

(a) State one substance from the table above that exists as(i) atoms.

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(ii) molecules.

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(iii) ions.

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(b) (i) What is the state of matter of magnesium at room temperature?

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(ii) Draw the particle arrangement in the substance you have stated in (b)(i).

(c) Magnesium has 12 protons in the nucleus of its atom. Draw the atomic structure of the magnesium atom.

(d) The diagram below shows the graph of temperature against time for the cooling of naphthalene.

(i) What is the melting point of naphthalene?

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(ii) Explain why the temperature does not change from X to Y.

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(iii) State how the movement of the naphthalene particles changes during the cooling process between W and X.

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Essay question

(a) Compare matter in solid, liquid and gas forms in terms of (i) the arrangement of particles (ii) the movement of particles

(iii) the force of attraction between particles(iv) the energy content

(b) By using the kinetic theory of matter, explain the change in the state of matter when a liquid boils to form a gas.

Paper 3

Referring to the statement above, plan one laboratory experiment to investigate the diffusion of particles in gas. Your plan should include the following:

(i) Problem statement (ii) Hypothesis(iii) List of substances and apparatus(iv) Procedure (v) Tabulation of data

The smell of the fried fish in the kitchen will spread to other locations in the house.