SMK BERANGAN, TUMPAT,
KELANTAN.
MONTHLY TEST (MARCH), 2007.
CHEMISTRY
(FORM FOUR)
Duration : 1 ½ hour
NAME : ………………………………………………………………………
FORM : ……………………………………….
INSTRUCTIONS :
1.
This paper consists of 3 structured questions
and 1 essay question.
2.
The mark is stated at the end of each question.
3.
The total marks for structured questions is 40 marks
and the marks given for an essay question is 10 marks.
4.
Answer all questions correctly and
briefly according to the marks given.
5.
A scientific calculator can be used in calculation.
6.
Show all the calculations needed.
7.
Answer the structured questions in the provided spaces
and answer the essay question in the given paper.
STRUCTURED QUESTIONS:
(40 marks)
-
An
experiment is carried out to determine the melting point of
naphthalene.
Thermometer
Boiling tube water
naphthalene powder
Figure 1
Naphthalene is heated in a water bath as shown in Figure 1.
The reading of thermometer is recorded at every two minutes
interval.
(a)
What is the purpose of using a water bath
? [ 2 marks ]
--------------------------------------------------------------------------------------------------
(b)
How does heating affect the kinetic energy of the
naphthalene particles ?
[ 2 marks ]
--------------------------------------------------------------------------------------------------
(c)
How does heating affect the distance between the
naphthalene particles ?
[ 2 marks ]
--------------------------------------------------------------------------------------------------
(d)
Given that the melting point of naphthalene is 800
C , sketch the graph of the thermometer readings against time
for this experiment. [ 2 marks ]
2 (a) Define valence electrons.
[ 2 marks ]
…………………………………………………………………………………
(b) The proton number of calcium is 20. Draw a diagram
showing the electronic
structure of calcium
atom.
[ 2 marks ]
(c ) Complete the table below :
|
Symbol |
Element |
Proton number |
Nucleon number |
Number of electrons |
Number of neutrons |
Electrons arrangement |
|
C |
Carbon |
6 |
12 |
|
|
2.4 |
|
F |
Fluorine |
|
19 |
9 |
|
2.7 |
|
Na |
Sodium |
11 |
|
|
12 |
2.8.1 |
|
Si |
Silicon |
|
|
14 |
14 |
2.8.4 |
|
Ar |
Argon |
18 |
40 |
18 |
|
|
[ 4 marks ]
(d) Define
isotopes.
[ 2 marks ]
………………………………………………………………………………….
(e)
There are two chlorine isotopes: namely Cl-35 and
Cl-37. Given that the proton number of chlorine is 17, what is
the number of neutrons in
(i) Cl-35 : ………………………………………….
(ii) Cl-37 : ………………………………………….
[ 2 marks ]
3(a) Calculate the relative molecular/ formula mass of the
following :
[ RAM: N;14 , O;16 , C;12 , H;1 , S;32 , Pb;207 , Cl;35.5 ,
Cu;64 ]
(i) Nitrogen dioxide, NO2
[ 2 marks ]
(ii) Glucose, C6H12O6
[ 2 marks ]
(iii) Lead(II) chloride, PbCl2
[ 2 marks ]
(iv) Anhydrous copper(II) sulphate, CuSO4 .
5H2O [ 2 marks ]
(b) Calculate the number of particles in
[ RAM : C;12 , O;16 , Ca;40 ]
(i) 88 g carbon
dioxide
[ 2 marks ]
(ii) 13.37 g
calcium
[ 2 marks ]
(c) Calculate the number of moles in
[ RAM : Ca;40 , Al;27 , S;32 , O;16 ]
(i) 2.408 x 1022 atoms of
calcium
[ 2 marks ]
(ii) 1.002 x 1024 aluminium ions in aluminium
sulphate [ 2 marks ]
(d) (i) Find the volume occupied by 48 x 1023
molecules of a gas at s.t.p.
[ Molar volume of gas at s.t.p. = 22.4 dm3 mol-1
;Avogadro constant = 6.02 x 1023 mol-1 ]
[ 2 marks ]
(ii) Find the number of molecules in 8.96 dm3 of
hydrogen at room condition.
[ Molar volume of gas at room condition = 24 dm3
mol -1 ]
[ 2 marks ]
ESSAY QUESTION
(10 marks)
-
Atoms are tiny indivisible particles of matter. They are too
small for anyone to
imagine how they actually like. Briefly outline how
scientists, beginning from
John Dalton to James Chadwick, slowly developed the
model of an atom.
*********** TRY YOUR BEST & GOOD LUCK
*************
PREPARED BY;
LATIFAH.S
