usbf 2 chem f4- with ans

8/4/2019 USBF 2 Chem F4- With Ans

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NAMA : __________________________________ MASA : 1 JAM

KELAS : __________ ________________________________________________________________________

Instruction to candidates:

Answer all questions in Section A by circling the correct answer. Answer all question in Section B

in the space provided.

________________________________________________________________________

Section A

1. Which of the following substances contain atoms?

A Zinc

B AmmoniaC Potassium iodide

D Lead (II) bromide

2. The melting points and boiling points of substance R and substance S are shown in table below.

Substance Boiling

point (0C)

Melting

point (0C)

R 78 6

S -115 -80

At room temperature, 24OC, R and S respectively, exists in the form of

A solid and liquid

B gas and solid

C liquid and gas

D solid and gas

3. Figure below shows the graph of temperature plotted against time when liquid S is cooled.

Which of the following statements is true?

1

SEKOLAH MENENGAH KEBANGSAAN RAJA PEREMPUAN,

IPOH

UJIAN SELARAS BERFOKUS 2/ 2008

CHEMISTRY T4



I M is in the solid state only, at level TU.

II M appears in the solid and liquid state at the level of ST.

III The forces of attraction between particles at S are very strong.

IV The kinetic energy of the particles at U are higher than particles at S.

A I and II only

B II and IV onlyC I, II and IV only

D I, II, III and IV

4. Sulphur-32 and Sulphur-34 are isotopes. The number of protons in the atom of Sulphur-32 is 16.

How many neutrons are present in the atom of Sulphur-34?

A 16

B 18

C 32

D 48

5. Atom Y has 23 subatomic particles in its nucleus and 11 electrons. Which of the followingstatements are true about atom Y?

I Y has a proton number of 11

II Y contains 12 neutrons

III Y contains 11 protons

IV

The symbol of an atom Y is 11

23

Y

A I and III only

B II and IV onlyC I, II and III only

D I, II, III and IV

6. Which of the following substances has the same empirical formula and molecular formula?

A Ethane, C2H6

B Propene, C3H6

C Ammonia, NH3

D Glucose, C6H12O6

7. Reaction between sodium hydroxide and sulphuric acid can be represented by the equation below.

2NaOH + H2SO4 Na 2SO4 + 2H2O

Which of the following statements about the equation shown above is true?

A Sodium hydroxide is the only reactant.

B 2 mole sulphuric acid is used in the reaction.

C 2 mole of sodium sulphate is produced in the reaction.

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D The product of the reaction is sodium sulphate and water.

8. The information below shows about two ion.

Ca2+

PO43-

Construct the chemical formula of the ionic compound formed by the following ions.

A CaPO4

B Ca2(PO4)3

C Ca2(PO3)4

D Ca3(PO4)2

9. Which of the following chemical equation is balanced?

A 2H2 + PbO Pb + 2H2O

B 2CuO + H2SO4 CuSO4 + H2OC 2Mg(NO3)2 2MgO + 4NO2 + O2

D CaCO3 + 2HCl CaCl2 + CO2 + H2O

10. Metal oxide R has the chemical formula R 2O3. The relative formula mass of the metal oxide

is 160. What is the relative atomic mass of metal R? [Relative atomic mass : O, 16]

A 42

B 56

C 68

D 84

11. One mole of oxygen gas contains

A 3.01 × 1023 atoms

B 3.01 × 1023 molecules

C 6.02 × 1023 atoms

D 6.02 × 1023 molecules

12. Which of the following is true about the Periodic Table ?

I Each horizontal row is called a period

II Each vertical columns is called a groupIII Each element in a group have similar chemical properties

IV Each group contains elements with similar chemical properties

A I and II only

B II and III only

C I, II and III only

D I, II, III and IV

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13. The elements in a group have similar chemical properties because they have the same number of

A protons in each of the atoms

B electrons in each of the atoms

C electron shells in each of the atoms

D valence electrons in each of the atoms

14. Which of the following is a special characteristic of transition elements ?

I Have catalytic properties

II Have low tensile strength

III Have variable oxidation numbers

IV Form coloured ions or compound

A I and II only

B II and III only

C I, III and IV only

D I, II, III and IV

15. The type of chemical bonds between two atoms by the transfer of electrons from a metal to a

non-metal is

A ionic bonds

B metallic bonds

C covalent bonds

D intermolecular bonds

---------15

Section B

1

.

Group

1 2 13 14 15 16 17 18

Figure 1

4

E G

J L M Q

R

T

Transition Element



Figure 1 shows the location for eight element E, G, J, L, M,Q, R and T in the Periodic Table.

Based on the Periodic Table in Figure 1 and use the alphabet given as the element symbol, answer

the following question..

a Four of the elements are metal. State those elements.

…J, L, R, T…………………………………………………………………………..[1 mark]

b Which element has the largest radius?

…T………………………………………………………………………………………

[1 mark]c Which element shown is the most reactive ? Explain Why.

T. Nuclear attraction towards the valence is weak for T. ThusT easily releases its valenceelectron to become ion.

[2 marks]

d Write the formula of the ion formed from L.

L3+ [1 mark]

e Write the electron arrangement for atom G.

2. 8 [1 mark]

f E can react with Q to form a compound.

I What is the type of bonding?

Covalent bonding [1 mark]

ii Draw the electron arrangement that formed in compound f(i).

[2 marks]

g J combines with Q to form a compound,Draw the electron arrangement of this compound.

[ 2 marks]

5



h. Write an equation for the reaction between R and Q.

R + Q2 RQ2 [1 mark]

2. Diagram below shows the electron arrangement for an atom T.

Atom T

a) i) Which period in the Periodic Table the T element is located.

Period 3[1 mark]

ii) Write the electron arrangement for the ion formed from T.

2. 8

[1 mark]

iii) Write half equation for the formation of T ion

T T2+ + 2e

[1 mark]

b) i) T atom reacts with flourine gas to form compound . [ F, Proton No: 9 ]Write the chemical formula for this compound

TF2

[1 mark]

ii) State the type of bond present in this compound

Ionic Bond[1 mark]

iii)

Draw the diagram of electron arrangement for the compound that is formed between Tand fluorine gas.

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[2 marks]

c) T atom reacts with oxygen gas to form T oxide. Write the chemical equation for thisreaction.

2 T + O2 2TO

[1 mark]

d) State two properties of compound formed in (c)

a) High m.p & b.p . b) Dissolves in water but does not dissolve in organic solvent.c) Conducts electricity in molten and aqueous state. ( Any 2 )

[2 marks]

3. An experiment is carried out to compare the reactivity of lithium, sodium and potassium.

(a) What are lithium, sodium and potassium known as?

Alkali metal [3 marks]

(b) In which group of the Periodic Table are lithium, sodium and potassium ?

Group I [3 marks]

( c) Lithium, sodium and potassium are burned in dry oxygen. Draw a diagram of theapparatus used to show the burning of these elements in oxygen in the laboratory.

7



[3 marks]

(d) Table 1 shows the results of the experiment. Complete the table.

Element Reaction with oxygen

Observation InferenceLithium Burns slowly with red flame. Lithium is reactive

Sodium Burns rapidly & brightly withyellow flame

Sodium is more reactive than lithium

Potassium Burns very rapidly & brightly with

purple / lilac flame.

Potassium is the most reactive of the

three elements.

[3 marks]

(e) Describe how lithium, sodium and potassium react with water. Write the balancedequations for these reactions.

Element Reaction with oxygen

Observation Inference Equation

Lithium Moves slowly on the

water surface with ‘hiss’sound. Colourless

solution that turn blue

litmus red is formed.

Reactive and forms an

alkaline solution.2 Li + H2O

2 LiOH + H2

Sodium Becomes a small sphereand moves rapidly on the

water surface with ‘ hiss’

sound. Colourlesssolution that turn blue

litmus red is formed.

Very reactive and forms analkaline solution.

2 Na + H2O 2 NaOH + H2

Potassium Becomes a small sphere,

burns with a purple / lilac

flame and moves veryrapidly with ‘hiss’ sound.

Colourless solution that

turn blue litmus red isformed

Very very reactive and

forms an alkaline solution.2 K + H2O

2 KOH + H2

8



[6 marks]

Prepared by: Checked by: Verified by:

……………………… ………………………. ……………………………….

(Pn. Mutulachimi M) (En. T.J. Pereira) ( En. M.Abu Bakar B. N.S M. Syarif)

Ketua Panitia Kimia Guru kanan Sains

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usbf 2 chem f4- with ans

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