L6 Finals P1 2010

CONFIDENTIAL*/SULIT* L6 FINALS 2009

STPM CHEMISTRY 962/1 1 [Turn over (Lihat sebelah)

CONFIDENTIAL*

SULIT*

SEKOLAH MENENGAH KEBANGSAAN BANDAR UTAMA

NO. 1, PINTASAN BANDAR UTAMA

47800 PETALING JAYA

PEPERIKSAAN AKHIR TAHUN OKTOBER 2010

CHEMISTRY PAPER 1 FORM LOWER 6 SCIENCE

1¾ HOURS ONE HOUR FORTY FIVE MINUTES

Instructions to candidate:

DO NOT OPEN THIS QUESTION PAPER UNTIL YOU ARE TOLD TO DO SO.

There are fifty questions in this paper. For each question, four suggested answers are given.

Choose one correct answer and indicate it on the multiple-choice answer sheet provided.

Read the instructions an the multiple-choice answer sheet carefully. Answer all questions.

Marks will not be deducted for wrong answers.

Arahan kepada calon:

JANGAN BUKA KERTAS SOALAN INI SEHINGGA ANDA DIBENARKAN BERBUAT

DEMIKIAN.

Ada lima puluh soalan dalam kertas ini. Bagi setiap soalan, empat cadangan jawapan

diberikan. Pilih satu jawapan yang betul dan tandakan jawapan itu pada helaian jawapan aneka pilihan yang dibekalkan.

Baca arahan pada helaian jawapan aneka pilihan itu dengan teliti. Jawab semua soalan. Markah tidak akan ditolak bagi jawapan yang salah.

This question paper consists of 11 printed pages.

(Kertas soalan ini terdiri daripada 11 halaman bercetak)

© Lau Kah Pew SMKBU 2010

Section A

Four suggested answers labelled A, B, C and D are given for each question. Choose one correct answer.

1. An element X with the electronic configuration of 1s22s

22p

63s

23p

63d

104s

24p

1 exist as

isotopes m

X and nX which have 38 and 40 neutrons respectively. What is the percentage

abundance of m

X? [Relative atomic mass of X is 69.7] (STPM 09 P1-1)

A) 35.0 B) 45.5 C) 54.5 D) 65.0



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2. A small spacecraft of capacity 10 m3 is connected to another of capacity 30 m

3. Before

connection, the pressure inside the smaller craft is 50 kPa and that inside the larger one is 100 kPa.

If all measurements are made at the same temperature, what is the pressure in the combined arrangement after the connection? (A-lvl(s) D90 P1-5)

A) 75 kPa B) 87.5 kPa C) 100 kPa D) 125 kPa

3. The value of PV is plotted against P for two gases, an ideal gas and a non-ideal gas, where P is the pressure and V is the volume of the gas.

Which of the following gasses shows the greatest deviation from reality?

A) methane C) ethene

B) ammonia D) carbon dioxide

4. A 2 g sample of hydrogen at temperature T and of volume V exerts a pressure P.

Deuterium, 2

1H, is an isotope of hydrogen.

Which of the following would also exert a pressure P at the same temperature T? (A-lvl(s) J98 P3-8)

A) 2 g of deuterium of volume V.

B) 4 g of deuterium of volume ½V.

C) a mixture of 1 g of hydrogen and 2 g of deuterium of total volume V.

D) a mixture of 2 g of hydrogen and 1 g of deuterium of total volume 2V.

5. When heated, solid iodine readily forms iodine vapour. What does this information suggest about the nature of the particles in these two physical states of iodine?

solid vapour

A) ionic atomic

B) ionic molecular

C) molecular atomic

D) molecular molecular

6. ABABA......... represents an arrangement of layers called

A) cubic closed packing C) face-centred closed packing

B) body-centred cubic packing D) hexagonal closed packing



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7. Graphite can be used as a lubricant, diamond cannot. This is because graphite has (A-lvl(s) D925 P4-18)

A) mobile delocalized electrons.

B) a hexagonal arrangement of atoms in layers.

C) covalent bonds between atoms in layers.

D) van der Waals’ forces between the layers of atoms.

8. Which of the following diagrams correctly represents the Boltzmann distribution of molecular speeds at two temperatures, T1 and T2; where T2 > T1? (A-lvl(s) D92 P4-6)

A)

C)

B)

D)

9. What is the maximum number of spectral lines that could be produced by electrons going

from n = 5 to n = 2, by all possible routes?

A) 2 B) 3 C) 4 D) 5

10. Which of the following is the best reason why electrons are treated as standing waves in

the modern quantum theory of the atom?

A) The wavelength of an electron depends on its velocity.

B) It is impossible to determine both the location and momentum of an electron.

C) An electron can remain in a particular orbit as long as it emits energy.

D) Spinning charged particles generate a magnetic field.

11. The rule which states that no two electrons in an atom can have the same set of quantum numbers is known as:

A) Hund’s rule C) Pauli’s exclusion principle

B) Aufbau principle D) Heisenberg’s uncertainty principle



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12. A line in the Pfund series (nlow = 5) occurs at 3.74 x 10-6

m. What is nhigh for this transition? The Rydberg constant equals 2.18 x 10

-18 J.

A) 6 B) 7 C) 8 D) 9

13. Which of the following elements has the highest second ionization energy? (A-lvl(s) D87 P3-1)

A) O B) Ne C) Na D) Mg

14. Which equation represents the ionisation energy of magnesium?

A) Mg(g) Mg+(g) + eˉ C) Mg(g) Mg

2+(g) + 2eˉ

B) Mg(s) Mg+(g) + eˉ D) Mg(s) Mg

2+(g) + 2eˉ

15. The first to fourth ionization energies of four elements are as follows:

Elements Ionization energy/kJ mol

-1

First Second Third Fourth

P 577 1 820 2 740 11 600

Q 418 3 070 4 600 5 860

R 736 1 450 7 740 10 500

S 494 4 560 6 940 9 540

Which statement about P, Q, R and S is TRUE? (STPM 09 P1-4)

A) Q is more electronegative than S.

B) Melting point of S is higher than that of R.

C) Enthalpy of vaporization of Q is higher than that of R.

D) Oxide Q is more basic than oxide P.

16. The ionic radii of four ions are as follows:

Ion Ionic radius/nm

P+

Q2+

R¯

S¯

0.095

0.031

0.136

0.126

Which ionic compound has bonding with the greatest covalent character? (STPM 08 P1-5)

A) PR B) PS C) QR2 D) QS2

17. Rank the following molecules in order of decreasing ionic character of their bonds.

SiCl2 NaCl PF3

A) NaCl > PF3 > SiCl2 C) NaCl > SiCl2 > PF3

B) SiCl2 > PF3 > NaCl D) PF3 > SiCl2 > NaCl



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18. Polyatomic molecules and ions have varied geometries. Which species and geometry corresponds CORRECTLY? (STPM 09 P1-6)

Species Geometry

A) NH2¯ Linear

B) H3O+ Trigonal planar

C) SiCl4 Square planar

D) ICl3 T-shape

19. Based on the band theory, the conductivity of metal is due to delocalized electrons in the conduction band. How many electrons are found in the conduction band of a 10.0 g magnesium metal strip?

[Relative atomic mass of Mg is 24.0; Avogadro constant is 6.02 x 1023

mol-1

] (STPM 09 P1-7)

A) 2.51 x 1023

C) 2.51 x 1024

B) 5.02 x 1023

D) 3.01 x 1024

20. VSEPR theory is a model for predicting

A) the strength of bonds C) how covalent bonding forms

B) the shape of molecules D) the type of bonding that occurs

21. The number of σ and π bonds respectively in O3 is:

σ bonds π bonds

A) 1 1

B) 2 1

C) 1 2

D) 2 2

22. Which molecule is planar?

A) NF3 B) C2Cl4 C) C3H6 D) NH4+

23. Which hybridisation occurs at the central atom for SF4 molecule?

A) sp2 B) sp

3 C) sp

3d D) sp

3d

2

24. MTBE is a constituent of petrol.

C

CH3

H3C O

CH3

CH3

angle P angle Q

What are the values of angle P and Q in the MTBE molecule?

angle P angle Q

A) 90º 105º

B) 90º 180º

C) 109.5º 105º

D) 109.5º 180º (A-lvl(s) J97 P3-4)



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25. Which of the following isomers is likely to have the highest boiling point?

A) CH3CHOHCH3 C) CH3CH2CH2CHO

B) CH3CH2CH2Cl D) CH3CH2CH2CH2CH3

26. Which of the following statements explain why copper conducts electricity when a potential difference is applied? (A-lvl(s) J91 P1-7)

A) electrons combine with the Cu2+

ion.

B) bonding electrons in the crystal lattice move.

C) Cu2+

ions move from the anode to the cathode.

D) electrons are excited from lower energy level to higher energy levels

27. Which type of bond is responsible for intermolecular forces in liquid nitrogen?

A) covalent bonding C) induced dipole-induced dipole attractions

B) hydrogen bonding D) permanent dipole- permanent dipole attractions

28. What is the bond angle around a triple bond?

A) 90º B) 109.5º C) 120º D) 180º

29. Trimethylamine, (CH3)3N, reacts with boron trifluoride, BF3, to form a compound of formula (CH3)3N·BF3.

How may this reaction be written in terms of the shapes of the reactants and products? (A-lvl(s) J95 P4-3)

A) NH3C

H3C

H3C

B

F

F F

+ NH3C

H3C

H3C

B

F

F F

B) NH3C

H3C

H3C

+ B F

F

F

N

CH3

CH3H3C

B F

F

F

C) NH3C

H3C

H3C

B

F

F F

+ NH3C

H3C

H3C

B

F

F

F

D) NH3C

H3C

H3C

+ NH3C

H3C

H3C

B

F

F

FB F

F

F



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30. Which of the following molecular structures below will have the smallest overall dipole?

A) C C

Cl

H3C Cl

CH3

C) C C

H3C

H3C Cl

Cl

B) C C

Cl

H3C CH3

Cl

D) C C

H3C

H3C CH3

Cl

31. The graphs of initial rate versus concentration of reactants for the reaction; X + Y Z, are shown below:

What is the order of reaction with respect to X and Y? (STPM 08 P1-8)

X Y

A) 0 1

B) 1 0

C) 1 2

D) 2 1

32. The following reaction is first order with respect to [P] and zero order with respect to [Q].

P + Q products

If the rate constant doubles for each 10ºC rise in temperature, which of the following sets of conditions will give the greatest rate of reaction? (A-lvl(s) J88 P3-12)

[P]/mol dm-3

[Q]/mol dm-3

Temperature/ ºC

A) 0.1 0.2 40

B) 0.1 0.3 30

C) 0.3 0.1 30

D) 0.3 0.1 20

33. For a first order reaction, rate constant is 0.6932 hr-1

. Determine the half-life for the

reaction.

A) 0.1 hr B) 1 hr C) 2 hrs D) 10 hrs



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34. For the reaction H2(g) + I2(g) 2HI(g), the rate of reaction is expressed as

A) t

HI

t

H

t

I

][

2

1][][ 22 C)

t

HI

t

I

t

H

][][

2

1][ 22

B) t

HI

t

H

t

I

2

][][][ 22 D) None of these

35. For the reaction; OCl̄ (aq) + I¯(aq) OI¯(aq) + Cl̄ (aq), the following data were collected at constant temperature.

What is the rate law for this reaction?

Experiment [OCl¯] [I¯] Rate (mol dm-3

s-1

)

1 1.7 x 10-3

1.7 x 10-3

1.75 x 104

2 3.4 x 10-3

1.7 x 10-3

3.50 x 104

3 1.7 x 10-3

3.4 x 10-3

3.50 x 104

A) Rate = k [OCl¯] C) Rate = k [OCl¯]2 [I¯]

B) Rate = k [OCl̄ ] [I¯] D) Rate = k [OCl¯] [I¯]2

36. The rate of a gaseous reaction is given by the expression k [A] [B]. If the volume of the

reaction vessel is suddenly reduced to ¼th of the initial volume, the reaction rate relating to original rate will be

A) 0.10 B) ⅛ C) 8 D) 16

37. The decomposition of hydrogen peroxide follows a first order kinetic. Which of the following graphs correctly represent this reaction?

A)

C)

B)

D)



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38. Which one of the following correctly represents the units of the rate constant, k, for a second order reaction?

A) s-1

B) mol dm-3

s C) mol dm-3

s-1

D) mol-1

dm3 s

-1

39. Consider the reaction:

S2O82-

(aq) + 2Iˉ(aq) 2SO42-

(aq) + I2(aq)

The rate equation is: Rate = k [S2O82-

] [Iˉ]; where k is the rate constant. Which of the following conclusions can be drawn from this information?

A) the reaction goes to completion

B) the reaction is second order with respect to Iˉ

C) the reaction is first order with respect to S2O82-

D) the value of k depends on the concentrations of S2O82-

and Iˉ

40. If a reaction involving a single reactant is first order with a rate constant of 4.50 x 10-2

s-1

, how much time is required for 75% of its initial concentration of reactant to be used up?

A) 16.7s B) 25.3s C) 23.1s D) 30.8s

Section B

For each of the questions in this section, one or more of the three numbered statements 1 to 3 may be correct. The responses A to D should be selected on the basis of the following.

A B C D

1 only

is correct

1 and 2 only

are correct

2 and 3 only

are correct

1, 2 and 3

are correct

41. Simple ionic crystals have good cleavage planes because the particles in the crystals are (A-lvl(s) D90 P1-33)

1. arranged in a regular lattice.

2. separated by large distances.

3. held by electrostatic forces.

42. Which of the following statements about the s, p and d orbitals of principal quantum

numbers 1, 2 and 3 are TRUE? (A-lvl(s) D90 P1-31)

1. Each s orbital can contain a maximum of two electrons

2. A series of transition elements arises from the filling of d-orbitals.

3. A p-orbital has a higher energy than the s-orbital of the same principal quantum number.



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A B C D

1 only

is correct

1 and 2 only

are correct

2 and 3 only

are correct

1, 2 and 3

are correct

43. Which of the following is/are part of Bohr’s interpretation of the hydrogen line spectrum?

1. different wavelengths of light correspond to electrons dropping between different quantum levels

2. electrons release energy as light as they move to a higher energy level

3. the potential energy of an electron decreases as it moves further from the nucleus

44. Choose the statement(s) that are TRUE

1. Outer electrons can penetrate the electron cloud of inner electrons.

2. Outer electrons experience partial nuclear charge

3. The 2s and 2p electrons are of different energy levels except in hydrogen atoms.

45. The Group 2 metals have higher melting points than the Group 1 metals.

Which factors could contribute towards the higher melting points? (A-lvl(s) J97 P3-35)

1. There are smaller interatomic distances in the metallic lattices of Group 2 metals.

2. Two valency electrons are available from each Group 2 metal atom for bonding the atoms into the metallic lattice.

3. Group 2 metals have higher first ionization energies.

46. The melting and boiling points of sulphur are higher than chlorine because…

1. Sulphur form larger and heavier molecules.

2. Chlorine has a higher relative atomic mass.

3. Sulphur molecules are more polarized compared to chlorine molecules.

47. The bond lengths and bond angles in the molecules of methane, ammonia and water may be represented as follows:

What causes this trend in the bond angles shown? (A-lvl(s) J92 P4-31)

1. Increasing repulsion between hydrogen atoms as the bond length decreases.

2. The number of non-bonding electron pairs in the molecule.

3. A non-bonding electron pair having a greater repulsive force than a bonding electron pair.



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A B C D

1 only

is correct

1 and 2 only

are correct

2 and 3 only

are correct

1, 2 and 3

are correct

48. Select the compound that has resonance structures

1. SO2

2. HCOO─

3. NO2

49. After an oil spillage at sea, a liquid hydrocarbon layer floats on the surface of the water.

Which of the following statement(s) help explain why liquid hydrocarbons both float on,

and are less dense water? (A-lvl(s) D90 P1-32)

1. There are only van der Waals’ interactions between hydrocarbon molecules.

2. Hydrogen bonding between molecules in liquid water causes them to pack closer together.

3. Hydrocarbon molecules are not solvated by water.

50. The rate equation for the reaction: 2A + B + C products; is

Rate of reaction = k [A] [B]2

It can be concluded that…

1. the overall order of reaction is 3

2. the rate of reaction will increase 8 folds when concentration A, B and C are doubled

3. the amount of products is not dependant on the amount of C used.

○○○ END OF QUESTION PAPER ○○○

Prepared by, Checked by, Verified by,

……………………… ………………………… …………………………

(LAU KAH PEW) Subject Teacher



CONFIDENTIAL*

SULIT*

Pro

port

ion o

f m

ole

cule

s

Molecular speed

T1

T2

PV

P

ideal gas

non-ideal gas

L6 Finals P1 2010

Documents

g of deuterium

g of hydrogen

volume v

g sample of hydrogen

total volume

pressure p

question paper

chemistry paper