Modul Latihan Kimia Tingkatan 4

1. Module 1
SECTION A
1 Graph 1 shows the temperature against time of solid substance X when heated. Substance
X is an organic compound and flammable.
GRAPH 1
(a) Draw a diagram of the set-up of the apparatus used to determine the melting point of
substance X.
[ 2 marks]
(b) (i) State the melting point of substance X
..................................................................................................................................
[ 1 mark]
1
Temperature / 0
C
Time/s
80
30 360
P
Q R
S

2. Module 1
(ii) What is the state of matter of substance X at :
PQ : ................................................................................................................................
RS : ...............................................................................................................................
[ 2 marks]
(iii) Explain why the temperature remains constant from Q to R?
.........................................................................................................................................
.........................................................................................................................................
[ 2 marks]
(iv) State how the movement of substance X particles changes between R and S
during heating.
………………………………………………………………………………………..
[ 1 mark]
(c) If substance X cooled to the room temperature without stirring, draw the graph of
temperature against time obtained.
[ 2 marks]
(d) Predict the substance X
................................................................................................................................................
[ 1 mark]
2

3. Module 1
2 Lactic acid is an acid produced in milk by bacteria, causes a sour taste. Table 2 shows the
percentage composition by mass of each element in lactic acid.
Element Percentage
Carbon 40.00
Hydrogen 6.67
Oxygen 53.33
TABLE 2
(a) Based on the information above, calculate the empirical formula of lactic acid.
[Relative atomic mass : H = 1 ; C = 12 ; O = 16 ]
[ 3 marks]
(b) Relative molecular mass of lactic acid is 90. Determine the molecular formula of lactic
acid.
[ 2 marks]
(c) Calculate the number of hydrogen atom in 1 mol of lactic acid?
[ NA = 6.02 × 10 23
]
[ 1 mark]
(d) Calculate the number of moles of 4.5 g lactic acid.
[Relative atomic mass : H = 1 ; C = 12 ; O = 16 ]
[ 1 mark]
3

4. Module 1
(e) Vinegar or ethanoic acid has a similar empirical formula with lactic acid.
(i) Given that three molecules of ethanoic acid have the same mass as two molecules of
lactic acid. What is the relative molecular mass of ethanoic acid?
[ 1 mark]
(ii) Determine the molecular formula of ethanoic acid.
[ 2 marks]
3 Table 3 shows formula of four ions.
Name of ions Silver ion Zinc ion Nitrate ion Chloride ion
Formula of ions Ag+
Zn2+
NO3
-
Cl-
TABLE 3
(a) Write the formulae for each compound below :
(i) Silver nitrate : .......................................................................................................
(ii) Zinc chloride : .......................................................................................................
(iii) Silver chloride : .......................................................................................................
(iv) Zinc nitrate : .......................................................................................................
[2 marks]
(b) When silver nitrate solution is added to zinc chloride solution, white precipitate, silver
chloride and zinc nitrate solution are formed.
(i) Identify the reactants and products of the reaction.
Reactants : ..................................................................................................................
Products : ..................................................................................................................
[2 marks]
(ii) Write the chemical equation for the reaction occurs in (b).
.......................................................................................................................................
[1 mark]
4

5. Module 1
(c) The following equation shows the decomposition of silver nitrate by heat.
2AgNO3 2Ag + 2NO2 + O2
If 85.0 g of silver nitrate is heated completely, calculate :
(i) the mass of silver formed.
[ Relative atomic mass : N =14; O = 16; Ag =108 ]
[ 3 marks]
(ii) the volume of oxygen gas formed at room conditions.
[ Molar volume : 24 dm3
at room conditions]
[ 2 marks]
5

6. Module 1
SECTION B
4 (a) Matter is made up of tiny and discrete particles.
(i) What is meant by matter?
[ 1 mark]
(ii) State 3 types of particle that made up matter.
[ 3 marks]
(b)
Based on the above situation, explain what happen refering to the kinetic theory of matter.
[ 2 marks]
(c) (i) Describe the experiment to determine the freezing point or the melting point of
naphthalene
(ii) Draw a labelled diagram of the experiment.
[ 14 marks]
5 (a) What is meant by the empirical formula ?
[ 1 mark]
(b)
 The colour of oxide M is green
 Metal M is grey
 Oxide M can be reduced to metal M when heated with hydrogen.
(i) Draw the labelled diagram of the experiment.
(ii) Describe the experiment conducted to determine the empirical formula of oxide M.
State the observation and precuationary steps taken in your experiment. Also show all
the calculation steps to get the empirical formula.
(iii) Write the chemical equation of the reaction.
[ Relative atomic mass : O = 16 ; metal M = 24 ]
[ 16 marks]
(c) The empirical formula of oxide M cannot be determine by heating oxide M with
magnesium. Explain why?
[ 3 marks]
6
You are shopping at the 2nd
floor of the shopping mall.
Suddenly you smell the delicious aroma of cookies being bake.
When you look down, there is the Famous Amos Cookies stall
on the first floor.

7. Module 1
SECTION C
[ PAPER 3 ]
6 A student carried out an experiment to determine the empirical formula of
magnesium oxide. Set-up of apparatus of the experiment are shown in Figure 6.
Step Set-up of apparatus
1
2
3
FIGURE 6
(a) State one observation and its related inference in the experiment
………………………………………………………………………………
………………………………………………………………………………
………………………………………………………………………………
………………………………………………………………………………
[ 3 marks]
7
Lid
Crucible
Digital
balance31.1745 g
Lid
Crucible
Digital
balance
Magnesium
ribbon
33.5744 g
lid
Crucible
Digital
balance
White magnesium
oxide powder
35.1744 g

8. Module 1
(b) Record the reading to two decimal places for :
The mass of crucible and lid = ………………g
The mass of crucible, lid and magnesium ribbon = ………………g
The mass of crucible, lid and magnesium oxide = ……………... g
[ 3 marks]
(c) (i) Calculate the mass of magnesium that has been used
[ 3 marks]
(ii) Calculate the mass of oxygen which reacted with magnesium
[ 3 marks]
(iii) Based on your answer in (c) (i) and (ii), how many moles of magnesium
and oxygen are there in the magnesium oxide used?
[Use the information that the relative atomic mass : Mg = 24 ; O = 16 ]
[ 3 marks]
(d) Determine the empirical formula of magnesium oxide.
[ 3 marks]
END OF QUESTION
8