Form 3 worksheet 2018
Module: Nature of matter
Topic: Atoms and Molecules and elements
1.
(a) Complete Fig. 2.1 to show the electronic structure of
31P.
15
P
[2]
Fig. 2.1
(a) Name the element shown above?
………………………………………………………………………..
[1]
(b) State the atomic number for the above element
………………………………………………………………………………
[1]
(c) State the atomic mass for the above element
……………………………………………………………………………….
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[1]
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Form 3 worksheet 2018
2. Fig. 1.1 represents the arrangement of atoms or molecules in four different substances, A,
B, C and D.
A
C
(a) Which substance is a diatomic molecule?
B
D
……………………………………………………………………
(i)
[1]
Explain your answer in (a)
………………………………………………………………………………………………………………………………………… [1]
(b) Which substance is an element?
…………………………………………………………………….
(i)
[1]
Explain your answer in (b).
………………………………………………………………………………………………………………………………………… [1]
3. Complete the following by filling in the blanks.
(a) An element is a pure substance containing only one kind of ____________.
(b) A molecule is a pure substance containing two or more _________________ chemically
combined.
(c) An element _____________ be separated into simpler materials (except during nuclear
reactions).
(d) Molecules can only be _____________________ separated, not physically.
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Form 3 worksheet 2018
Topic: Periodic table
1. Fig. 1.1 shows the electronic structure of an atom of chlorine.
Fig. 1.1
(a) (i) State the Group of the Periodic Table in which chlorine is placed.
................................................................................................................
[1]
(ii) Use the information in Fig. 1.1 to give a reason for your answer to (a)(i).
……………………………………………………………………………………………………………………………………….
…………………………………………………………………………………………………………………….…………… [1]
(b)
(i) state the period of the periodic table in which chlorine is placed.
.................................................................................................................
(ii)
[1]
Use the information in Fig 1.1 to give a reason for your answer to (b) (i).
………………………………………………………………………………………………………………………………………… [1]
2. Explain the periodic trend of elements in a periodic table in terms of:
(a) Metallic and non metallic properties:
………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………….. [2]
(b) Reactivity
……………………………………………………………………………………………………………………………………..
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Form 3 worksheet 2018
3. The electronic structures of various atoms are shown below.
A
B
D
C
E
(a) (i) Which one of these structures A to E represents a noble gas?
[1]
(ii) Which two of these structures represent atoms from the same Group of the Periodic
Table?
and
[1]
(iii) Which one of these structures represents an atom with an atomic number of 8?
[1]
(iv) Which one of these structures is in Period 3 of the Periodic Table?
…………………………………………………………………………………………………………………………………. [1]
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Form 3 worksheet 2018
4. Table 5.1 shows the elements of the third period of the Periodic Table with their
electronic structures.
Table 5.1
III
Group
IV
I
II
Na
Mg
Al
Si
2,8,1
2,8,2
2,8,3
2,8,4
V
VI
VII
0
P
S
Cl
Ar
2,8,5
2,8,6
2,8,7
2,8,8
(a) Describe how the metallic character of these elements changes across the period.
……………………………………………………………………………………………………… [1]
(b) State the relationship between the metallic character of an element and its electronic
structure.
………………………………………………………………………………………………………. [1]
(c) State and explain which period these elements belong to?
…………………………………………………………………………………………………………
………………………………………………………………………………………………………. [2]
(d) Draw the electronic structure of aluminum.
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Form 3 worksheet 2018
5. Figure 3 shows the electron arrangement of a different atom from an element in the
second row of the periodic table.
(a) Give the chemical symbol of this element.
................................................................................................................................................................... [1]
(b) Why is this element unreactive?
……………………………………………………………………………………………………………………………………………………………. [1]
6. Figure 2 shows the electron arrangements of three different atoms, X, Y and Z.
These atoms are from elements in the second row (lithium to neon) of the periodic table.
Figure 2
(a) Which atom is from an element in Group 3 of the periodic table?
………………………………………………………………………………………………………. [1]
(b) Explain ……………………………………………………………………………………………
………………………………………………………………………………………………………. [1]
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Form 3 worksheet 2018
7. Elements are made of atoms.
Table 1 shows the atomic numbers and mass numbers of three atoms.
Table 1
Atom
Atomic number
Mass number
1
12
24
2
12
25
3
12
26
(a) Suggest, in terms of the number of subatomic particles, why the atomic numbers of the
three atoms are the same.
………………………………………………………………………………………………………… [1]
(b) Explain, in terms of the number of subatomic particles, why the mass numbers of the
three atoms are different.
………………………………………………………………………………………………………… [1]
(c) What is the common name for elements with the same atomic number?
………………………………………………………………………………………………………… [1]
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Form 3 worksheet 2018
Topic: Compounds and Mixtures
1. State which of the following statements best describes a Compound or Mixture.
(a) Can be separated into their components by chemical or physical
means……………………....
(b) Properties are usually different than the properties of the elements it contains.
…………………………….
(c) A pure substance containing two or more kinds of elements.
……………………………………….
(d) Properties are similar to the properties of its components. …………………………… [4]
2. which box (A,B,C,D,E) represents an element, compound, molecule and mixture.
A
B
A ………………………………………………….
C
D
E
B ………………………………………………….
C ………………………………………………….
D ………………………………………………….
E …………………………………………………...
[5]
3. the following are the chemical formulae of some compounds, for each one say what the
constituents are?
(a) C2H6
…………………………………………………………………………………………………………………………… [1]
(b) ZnCl2
…………………………………………………………………………………………………………………………… [1]
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Form 3 worksheet 2018
(c) CuCO3
…………………………………………………………………………………………………………………………… [1]
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Form 3 worksheet 2018
Topic: Heating and Cooling curve
Kagiso was given ice blocks to determine the boiling point of water. He presented his result on a
graph below.
Study the heating curve below to answer questions that follow.
1. (a) Explain what is happening to the average kinetic energy of the particles in the sample during
section 2?
……………………………………………………………………………………………………………………………………………….
……………………………………………………………………………………………………………………………………….. [2]
(c) For section 3, explain why the temperature does not remain constant?
……………………………………………………………………………………………………………………………………………….
…………………………………………………………………………………………………………………………………………. [2]
(d) State the boiling point of this substance?
………………………………………………………………….
[1]
(e) State the melting point of this substance?
…………………………………………………………………
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Form 3 worksheet 2018
Topic: Separation Techniques
1. The diagrams show four methods of purifying substances.
ethanol
vapour
filter paper
ethanol
heat
(c)
A
B
C
D
Which of these methods, A,B,C or D, is best used for
(i) separating the different colours in a sample of ink?.........................
[1]
(ii)
separating two liquids with different boiling points? …………………
[1]
(iii)
separating mud from water? …………………………………
[1]
(iv)
making crystals of copper sulphate from copper sulphate solution? ……………………..
[1]
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Form 3 worksheet 2018
(b) State the name given to the method of separation shown in
(i) diagram A, .................................................................................................................
(ii) diagram B. ................................................................................................................. [2]
2. Plants make a variety of coloured pigments. A student extracted red colouring from four
different plants, R, S, T and U. The student put a spot of each colouring on a piece of filter
paper. The filter paper was dipped into a solvent and left for 30 minutes. The results are
shown below.
start of experiment
result after 30 minutes
filter paper
R S T U
R S T U
solvent
(i) What is name given to the process shown in the diagram?
[1]
(ii) Which plant contained the greatest number of different pigments?
[1]
(iii) Which two plants contained the same pigments?
……………………………………………………………………………………………………………………………… [1]
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Form 3 worksheet 2018
The diagram below shows a chromatogram obtained using solutions of three single dyes of
colours blue, green and red three other samples H,I, and J. Use it to answer question 9.
3
(i)
(a) Which of the samples H, I and/or J contain the following;
One dye only?
………………………………………………………………………………………………. (1)
(i)
A dye other than blue, green or red?
………………………………………………………………………………………………. (1)
(b) Which dye is present in all samples?
……………………………………………………………………………………………… (1)
(c) Explain why the starting line of the chromatogram should be drawn with a pencil rather than
with ink.
………………………………………………………………………………………….………………………………………………………
…………………………………………………………………………………….……………………………………………………… (2)
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Form 3 worksheet 2018
Use the information and the diagram below to answer question 4.
Traditional alcohol is made by mixing malt powder, sugar and plenty of water. The mixture is
allowed to ferment for 2-3 days in a warm room. The mixture is then boiled to separate the
traditional alcohol as shown in the set-up below.
4.a) Name the separation technique used above.
………………………………………………………………………………………………………………………………….. (1)
b) In this set- up, what is the purpose of the cold water in the trough?
………………………………………………………………………………………………………………….……………... (1)
c) Explain why the pipe passing through the trough is at the bottom rather than at the
top.
……………………………………………………………………………………………………………………………
……………………………………………………………………………………………………………………………
………………………………………………………………………………………………………………………….(3)
(g) Drinking water can be obtained by purifying seawater.
Explain why distillation rather than filtration is used to purify seawater for drinking.
[2]
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Form 3 worksheet 2018
4. Petroleum (crude oil) is a fossil fuel consisting of a mixture of different hydrocarbons.
Fig. 4.1 shows the industrial apparatus used to separate useful products from
petroleum.
refinery gases
tower
naphtha
petroleum
vapour in
bitumen
Fig. 4.1
Petroleum is vaporised and passed up a tower. Useful products from petroleum condense at
different positions in the tower.
(a) State the name of the process shown in Fig. 4.1.
……………………………………………………………………………………………………… [1]
Different products from this process have different boiling point ranges.
(b) State how the boiling point of a product affects the position in the tower where a product
will condense.
…………………………………………………………………………………………………………
………………………………………………………………………………………………………. [1]
(c) Three of the useful products obtained from petroleum are shown in Fig.
4.1. State the name of another useful product that is separated from
petroleum. …………………………………………………………………………
[1]
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Form 3 worksheet 2018
5. The student wanted to separate the solid yeast from the solution.
Figure 10 shows the apparatus used.
Figure 10
Conical flask
Mixture of
solution
and yeast
Funnel
Beaker
(a) What is missing from the apparatus in Figure 10?
……………………………………………………………………………………………………… [1]
(b) Name the solution collected in the beaker.
………………………………………………………………………………………………………. [1]
(c) Name the above technique of separation.
………………………………………………………………………………………………………. [1]
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Form 3 worksheet 2018
6. Some plants contain oils that can be extracted.
Figure 3 shows a process used to separate oils from plants.
(a)
What is the name of this process?
Tick () one box.
[1]
Displacement
Distillation
Pressing
(b) Describe the change of state at S.
…………………………………………………………………………………………………………. [1]
(c) Describe the change of state at T.
…………………………………………………………………………………………………………. [1]
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Form 3 worksheet 2018
7. A student was asked to separate a mixture consisting of copper metal powder and sodium
chloride powder. Copper metal powder is insoluble in water. Sodium chloride powder is
soluble in water.
Using the list of apparatus and materials below, describe a procedure that the student can
follow to obtain copper metal from the mixture. You may use a diagram to support your
answer.
…………………………………………………………………………………………………………
…………………………………………………………………………………………………………
…………………………………………………………………………………………………………
…………………………………………………………………………………………………………
…………………………………………………………………………………………………………
…………………………………………………………………………………………………………
…………………………………………………………………………………………………………
…………………………………………………………………………………………………………
…………………………………………………………………………………………………………
…………………………………………………………………………………………………………
…………………………………………………………………………………………………….. [5]
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Form 3 worksheet 2018
8. The set-up below was used to illustrate how salty water can be desalinated.
(a) Name the desalination method used.
……………………………………………………………………………………………………… [1]
(b) Describe how pure water is obtained in the desalination process illustrated above.
…………………………………………………………………………………………………………...
…………………………………………………………………………………………………………...
…………………………………………………………………………………………………………...
………………………………………………………………………………………………………. [3]
(c) Ice- cubes are to be added to water from time to time.
Explain what will happen if ice- cubes are not added?
…………………………………………………………………………………………………………
………………………………………………..……………………………………………………. [2]
(d) State two physical properties of water.
…………………………………………………………………………………………………………..
……………………………………………………………………………………………………… [2]
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Form 3 worksheet 2018
Module: Acids and Bases
Topic: Classes of Acids and Bases
1. The diagram shows the changes in pH in a student’s mouth after she has eaten a sweet.
7
6
pH
5
4
3
0
10
20
30
40
50
time / minutes
(a) Describe how the acidity in the student’s mouth changes after she has eaten the sweet.
[2]
(b) (i) Chewing a sweet stimulates the formation of saliva. Saliva is slightly alkaline. Use
this information to explain the shape of the graph.
[2]
(ii) State the name of the type of reaction which occurs when an acid reacts with an alkali.
[1]
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Form 3 worksheet 2018
2. A student used the apparatus shown below to calculate the concentration of a solution of
calcium hydroxide.
A
hydrochloric acid
calcium hydroxide solution
(a) State the name of the piece of apparatus labelled A.
…………………………………………………………………………………………………………………………………………. [1]
(b) Describe how the pH of the solution in the flask changes as the hydrochloric acid is added.
……………………………………………………………………………………………………………………………………………….
……………………………………………………………………………………………………………………………………….. [2]
(c) State the colour on the universal indicator for the following solutions:
i)
Hydrochloric acid ………………………………………………………………………………………….. [1]
ii)
Calcium hydroxide ………………………………………………………………………………………… [1]
(d) Define the term pH
……………………………………………………………………………………………………………………………………………….
…………………………………………………………………………………………………………………………………………. [1]
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Form 3 worksheet 2018
3. Use the information below to answer questions that follow.
20 % of Sodium hydroxide and 40% of hydrochloric acid will completely ionize in water
forming hydroxyl ions and hydrogen ions. 90% of Ammonia and 70% of Ethanoic acid
will partially ionize in water to release same ions listed above.
(a) What is the concentration and strength of:
i.
Sodium hydroxide
…………………………………………………………………………………… [1]
ii.
Hydrochloric acid
…………………………………………………………………………………… [1]
iii.
Ammonia
………………………………………………………………..………………….. [1]
iv.
Ethanoic acid
……………………………………………………………………………………. [1]
(b) Complete the word equations below:
i.
Hydrochloric acid
water
___________________ + ____________ [1]
ii.
Ammonia + water  ___________________ + _____________________ [1]
4. State two differences between strong acids and weak acids.
Strong acids
Weak acids
5. Copper oxide and sodium hydroxide both will turn red litmus paper blue, explain why though
having same property the two chemicals are different?
……………………………………………………………………………...………………………………………………………………
……………………………………………………………………………………………………………………………………………..
………………………………………………………………………..………………………………………………………………. [2]
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Form 3 worksheet 2018
Topic: Reaction of Acids with other chemicals
1. Ammonium nitrate can be made by adding nitric acid to a solution of ammonia.
(i) What type of reaction is this?
[1]
(ii) State two application of this type of reaction in everyday life.
……………………………………………………………………………………………...………………………………………...
…...……………………………………………………………………………………….…………………………………….. [2]
(iii) Complete the word equation for this reaction.
Ammonia + nitric acid
Ammonium nitrate + ……………………………………………….………….… [1]
2. (i) Complete the following equation for the reaction of calcium carbonate with hydrochloric
acid.
Calcium carbonate +
………………………… + carbon dioxide + water
acid
(ii)
Describe how you would test for the gas given off in this reaction.
Test............................................................................................................................
Result.........................................................................................................................
(iii)
[3]
State any two application of acid-carbonate reaction in everyday life.
……………………………………………………………………………………………………………………………………………….
………………………………………………………………………………………………………………………………………… [2]
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Form 3 worksheet 2018
3. The student adds a 2 cm length of magnesium ribbon to a fresh supply of hydrochloric acid.
He measures the total volume of gas collected every 30 seconds for 3 minutes.
He plots his results as shown in Fig. 6.1.
25
total
volume
of gas
collected
3
/ cm
20
15
10
5
0
0
0.5
1.0
1.5
time / min
2.0
2.5
3.0
Fig. 6.1
(a) Describe what happens to the rate of this reaction during the 3 minute period.
…………………………………………………………………………………………………………...
…………………………………………………………………………………………………….. [2]
(b) Suggest a reason for the rate of reaction between 2.5 and 3 minutes.
…………………………………………………………………………………………………………
………………………………………………………………………………………………………. [1]
(d)
He does a second experiment with a new 2 cm length of magnesium ribbon and the
same volume and concentration of acid, but at a higher temperature.
Draw on Fig. 6.1 the curve that the student draws. Label your curve T.
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[2]
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Form 3 worksheet 2018
4. (a) Complete the equation for the reaction of hydrochloric acid with zinc.
Zinc + hydrochloric acid
zinc chloride + ……………….……………
[1]
(c) Name the type of reaction above?
……………………………………………………………………………………………………………………………………………….. [1]
(d) Describe how you will test for the gas.
Test …………………………………………………………………………………………………………………………………… [1]
Results ………………………………………………………………………………………………………………………………. [1]
(e) State one application of the above type of reaction.
………………………………………………………………………………………………………………………………………………. [1]
4. (a) Fig. 1.1 shows an experiment to compare how three metals react with dilute
hydrochloric acid.
In two of the test-tubes, bubbles of a gas G are produced. Gas G is an element.
(i)
State the name of gas G.
……………………………………………………………………………………………...…… [1]
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Form 3 worksheet 2018
(ii)
Describe a test for gas G.
Test
………………………………………………………………………………………………………………………….. [1]
Result
………………………………………………………………………………………………………………………. [1]
(iii)
List the four elements X, copper, magnesium and G in order of
reactivity. most reactive
least reactive
[2]
(iv) Suggest the identity of metal X.
[1]
5. A sample of soil is mixed with water and filtered.
(a) Describe a test that would show that the soil is acidic.
..................................................................................................................................
............................................................................................................................. [2]
In order to reduce soil acidity, limestone is sometimes added.
Limestone consists mainly of calcium carbonate.
(b) Complete the word equation for the reaction occurring between calcium carbonate and
dilute hydrochloric acid.
Calcium
carbonate
+
hydrochloric
carbon
acid
dioxide
+
+
...................................
(c) The soil treatment described in (b) adds to the amount of carbon dioxide in the atmosphere.
(i) Describe how this increase could be affecting the environment.
……………………………………………………………………………………………………………………
………………………………………………………………………………………………………………… [2]
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Form 3 worksheet 2018
3. Figure 1 shows apparatus used to investigate the reaction of sulfuric acid
with calcium carbonate.
(a) Explain any two changes observed in the investigation above.
…………………………………………………………………………………………………………
…………………………………………………………………………………………………………
…………………………………………………………………………………………………………
…………………………………………………………………………………………………… [4]
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Form 3 worksheet 2018
Topic: Rate of chemical reaction
1.
A student investigates the reaction between zinc and hydrochloric acid. The
hydrochloric acid is in excess. The student uses the apparatus shown in the
diagram.
gas
syringe
gas
small test
tube held by
a piece of
cotton
zinc powder
hydrochloric acid
(a) Write a complete word equation for the above reaction.
Zinc + Hydrochloric acid
…………………………………………….. + ………………………………………. [2]
(b) The student reads the volume of gas in the syringe every
minute. The results are shown in the table.
time in minutes
0
1
2
3
4
5
6
7
volume of gas in cm3
0
23
35
45
50
53
55
55
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Form 3 worksheet 2018
(i) Plot the results on the grid on page 18.
60
50
40
30
20
10
0
(ii)
1
2
3
4
5
6
7
time / min
Explain why the volume of gas stays the same after six minutes.
...................................................................................................................................................................................................
...............................................................................................................................................................................
[2]
(iii)
The student does the experiment again. The only difference is that the student uses
warm, rather than cold, hydrochloric acid. On the grid, draw the shape of the graph you
would expect for the experiment with the warm hydrochloric acid.
[2]
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Form 3 worksheet 2018
2. A student used the apparatus shown below for investigating the speed of the reaction
between iron and sulphuric acid.
Sulphuric
water
Acid
iron powder
(a) The student repeated the experiment with different concentrations of sulphuric acid. In
each experiment the mass of iron powder was the same and the temperature was kept at
30°C.
The results are shown in the table.
concentration of sulphuric
acid / moles per dm3
speed of reaction /cm3
hydrogen per second
0.4
4.2
0.8
8.5
1.6
17.0
(i)
Use the information in the table to help you work out how the speed of the
reaction is affected by the concentration of sulphuric acid.
[2]
(d)
What will happen to the speed of the reaction if lumps of iron are used
instead of iron powder?
[1]
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Form 3 worksheet 2018
3. Catalyst X was added to 50cm3 of hydrogen peroxide solution at 20oC and the
amount of oxygen given off was recorded over a two minute period. The
experiment was repeated with the same amounts of catalyst Y and catalyst Z.
Apart from the type of catalyst, all conditions were kept the same in the three
experiments. A graph of the results is shown below.
(i) What is a catalyst?
………………………………………………………………………………………………………………………………… [1]
(ii) Which catalyst, X, Y or Z, produced oxygen gas the fastest?
Explain your answer.
[2]
(iii) Why is the final amount of oxygen gas the same in each experiment?
[1]
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Form 3 worksheet 2018
Use the diagram and the information below to answer question 3 (a) to (d)
The diagram shows a set-up used to compare the reaction of calcium with water and that of barium
with water. To make the comparison of the reactions fair, the mass of barium and the mass of
calcium should be the same. The two metals are found in group 2 in the Periodic Table.
4. (a) Name gas Y.
..................................................................................................................................
(1)
(b) Suggest two other factors which should be the same to make the comparison fair.
...............................................................................................................................................................................................
...................................................................................................................................................................................... (2)
(c) After two minutes from the start of the experiment, the plunger of the syringe in the barium
experiment had moved out further than in the calcium experiment.
Explain this observation.
...............................................................................................................................................................................................
....................................................................................................................................................................................... (1)
(d) Which substance other than water can be used in the experiment?
........................................................................................................................................................................................ (1)
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Form 3 worksheet 2018
5. A student investigates the speed of reaction between dilute hydrochloric acid and
calcium carbonate.
The reaction produces carbon dioxide gas.
(d) Fig. 2.1 shows some of the apparatus the student uses.
(i) The student wants to measure the volume of gas produced in this reaction every minute
for 10 minutes.
Complete Fig. 2.1 to show how the student collects and measures the volume of gas. [2]
(ii)
Describe the test for carbon dioxide gas.
test ...........................................................................................................................
result .............................................................................................................................. [2]
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Form 3 worksheet 2018
(iii)
As the reaction proceeds, the acid concentration
decreases. Describe what happens to the speed of the
reaction.
............................................................................................................................. [1]
6. Fig 4.1 shows apparatus some students use to investigate the effect of temperature on
the rate of reaction between calcium carbonate and dilute hydrochloric acid.
Table 4.1 shows the results of the investigation.
Table 4.1
temperature / °C
time taken to fill the gas jar / s
20
156
30
75
40
37
50
20
60
10
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Form 3 worksheet 2018
(a) Use Table 4.1 to state how the rate of reaction changes when the experiment is
repeated at higher temperatures.
..................................................................................................................................
............................................................................................................................. [1]
(b) Explain your answer to (a) in terms of the collisions between particles.
..................................................................................................................................
..................................................................................................................................
..................................................................................................................................
............................................................................................................................. [2]
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Form 3 worksheet 2018
Module: Metals and Non Metals
Topic: Properties and uses of Metals and Non Metals
1. State three physical properties which are characteristic of all metals.
[3]
2. State three physical properties which are characteristic of all non metals.
…………………………………………………………………………………………………………………………………………
…………………………………………………………………………………………………………………………………………
…………………………………………………………………………………………………………………………………… [3]
3. List three most reactive metals.
……………………………………………………………
…………………………………………………………..
…………………………………………………………..
[3]
4. List three most unreactive metals.
……………………………………………………………
……………………………………………………………
……………………………………………………………
[3]
5. Explain the meaning of the following terms in terms of metals and non metals.
(a) Ductile
…………………………………………………………………………………………………………………………………… [1]
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(b) Brittle
…………………………………………………………………………………………………………………………………… [1]
(c) Malleable
………………………………………………………………………………………………………...…………………………. [1]
(e) The list below shows some of the substances which are found in the liquid which drains
through the waste.
Aluminium
Oxygen
calcium carbonate
phosphorus
iron
lead
chlorine
magnesium
nickel
sodium sulphate
zinc
From this list choose
(i) a metal used to galvanise iron. .................................................................................
(ii) a transition metal. ...........................................................................................................
(iii) a metal which is in Group IV of the periodic table. ....................................................
(iv) a metal which is used to make aircraft bodies. .......................................................
(v) a non-metallic gas that supports burning ………………………………………………
(vi) a non-metallic solid used in matches ………………………………………………………
(vii) a non-metallic gas used to sterilize water ……………………………………………….
[7]
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6. A piece of sodium metal attached to a copper wire was left for a few days as shown in
the diagram below. Use the diagram to answer question 6.
(a) The sodium reacted with one of the gases in the air under the test tube to form an oxide.
(i) Name the gas that reacted with sodium?
………………………………………………………………………………………………… [1]
(ii)
Write the word equation for the reaction
………………………………………………………………………………………………… [2]
(iii)
What happened to the water level inside the test tube after the reaction?
………………………………………………………………………………………………… [1]
(iv)
Explain your answer in (iii)
………………………………………………………………………………………………… [1]
(b) Give one physical property of water.
…………………………………………………………………………………………………….. [1]
(c) Name one element found in the same group with sodium in the periodic table.
……………………………………………………………………………………………………... [1]
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Form 3 worksheet 2018
7. The diagram below shows a piece of magnesium ribbon burning in air. Use it to answer
question 7.
(a) Name the substance that reacted with magnesium ribbon to form white powder.
...………………………………………………………………………………………………… [1]
(b) What is the chemical name for the white powder formed?
...………………………………………………………………………………………………… [1]
(i) Is the white powder an element or compound?
…………………………………………………...………………………………………………….. [1]
(ii) Explain
………………………………………………………………………………………………………. [1]
(c) Magnesium can also react with dilute acids.
(i) Name any acid that can react with magnesium.
………………………………………..………………………………………………………… [1]
(ii) Write the word equation for the reaction between magnesium and the acid you
named above.
………………………………………………………………………………………………….. [2]
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Topic: The chemical process of rusting
1.
When Group I elements react with water, hydrogen gas is given off.
The diagram shows the reaction of lithium, potassium and sodium with water.
A
B
C
(a) Which one of these elements A, B or C is lithium?
[1]
(b) (i) Write the equation for the reaction of sodium with water by completing the
right-hand side.
sodium + water
………………………….. + …………………………….
[1]
(ii) Apart from fizzing, describe two things that you would see when sodium
reacts with water.
[2]
(iii) After the sodium had reacted with the water, the solution was tested with
red litmus paper.
What colour did the litmus paper turn?
Give a reason for your answer.
colour
Reason
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[2]
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Form 3 worksheet 2018
2. The diagram shows an experiment to investigate the rusting of some iron nails.
A
B
C
Air
air
Air
iron nail
iron nail
iron nail
coated with
Zinc
Distilled
Water
drying agent
(calcium chloride)
Distilled
Water
(a) For each tube A, B and C predict whether the nails will rust. In each case give a reason.
tube A: does the nail rust?
reason
tube B: does the nail rust?
reason
tube C: does the nail rust?
reason
[3]
3. Complete the word equation for rusting.
iron + ……………………….. + oxygen
…………………………..
[1]
4. State two conditions needed for rusting to occur.
………………………………………………………………………………..
………………………………………………………………………………..
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[2]
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5. Write the chemical name for rust.
………………………………………………………………………………………………………………………………………… [1]
6. State four ways by which rusting can be prevented.
………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………… [4]
7. Define the following terms:
(a) Oxidation
………………………………………………………………………………………………………………………………………………
………………………………………………………………………………………………………………………………………… [1]
(b) Corrosion
………………………………………………………………………………………………………………………………………………..
…………………………………………………………………………………………………………………………………………. [1]
(c) Rusting
………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………… [1]
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Topic: Carbon
1. Define the term allotrope.
………………………………………………………………………………………………………………………………………………
………………………………………………………………………………………………………………………………………… [1]
7
Three forms of carbon are diamond, graphite and Buckminsterfullerene.
carbon
atom
diamond
graphite
(a) State two differences in structure between graphite and diamond.
…………………………………………………………………………………………………………………………………………
………………………………………………………………………………………………………………………………………….
…………………………………………………………………………………………………………………………………………
………………………………………………………………………………………………………………..…………………… [2]
(b) State the type of bonding between the carbon atoms in diamond.
………………………………………………………………………………………………………………………………………… [1]
(c) Suggest why graphite is used as a lubricant.
Refer to the layers in your answer.
...........................................................................................................................................
.....................................................................................................................................
[1]
(d) Which of the two allotropes conduct electricity? Explain your answer.
.....................................................................................................................................................................................
………………………………………………………………………………………………………………………………… [1]
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Topic: Mining Techniques
1. The iron from the blast furnace contains up to 10% by mass of impurities. Use the blast
furnace below to answer questions that follow.
oxygen and powdered
limestone
slag forming
molten iron from
blast furnace
A mixture of oxygen and limestone is blown onto the surface of the molten iron.
(a) What is the purpose of blowing oxygen onto the molten iron?
[1]
i)
Write the word equation for the above chemical reaction.
Oxygen + …………………………………
heat + …………………………………..
[1]
The limestone added breaks down to form a basic oxide. The basic oxide reacts with the impurities
in the iron and form a slag.
(b) Complete the following word equations about the two chemical reactions explained above.
Calcium carbonate
………………………………….. + Carbon dioxide
calcium oxide + ……………………………….
calcium silicate
(c) What information in the diagram suggests that the slag is less dense than the molten iron?
…………………………………………………………………………………………………………………………………… [1]
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2. Name at list one ore of iron.
…………………………………………………………..
[1]
3. Name three raw materials added into the blast furnace.
…………………………………………………………….
…………………………………………………………….
…………………………………………………………….
4. List at list two impurities found in the carbon ore.
……………………………………………………………….
………………………………………………………………
[2]
5. List two uses of iron.
…………………………………………………………………………………………………………………………………………
…………………………………………………………………………………………………………………………………… [2]
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Form 3 worksheet 2018
Topic: Extraction of Copper
1. The diagram below shows extraction of copper in Bcl mine. Use it to answer questions
that follow.
(a) State at list one ore of copper.
………………………………………………………………………
[1]
(b) State two impurities in copper ore.
……………………………………………………………………..
……………………………………………………………………..
[2]
(c) Complete the word equation below.
Copper sulphide + copper oxide
(d) Label stage X on the diagram.
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Sulphur dioxide + …………………………………
[2]
[1]
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Form 3 worksheet 2018
Module: Motion
1
Fig. 1.1 shows a car travelling at 30 m/s on a level road. At this speed the car has to overcome a
force opposing the car.
opposing force
driving force
Fig. 1.1
(a) The engine of a motor car is able to deliver a force of 80N to the wheels. If this force is able
to accelerate the car at 3.8 m/s2, what is the mass of the motor car?
…………………………….Kg [2]
(b) Calculate the distance travelled by the car at the speed of 30m/s in 10s.
………………………… m [2]
(c) Explain why the car slows down when it climbs a hill, even though the driving force is
unchanged.
..........................................................................................................................................
..........................................................................................................................................
.......................................................................................................................................... [1]
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2. A soccer ball lies on a grass surface and is given a kick so that it starts rolling at 40 m/s.
the ball stops rolling after 3 seconds. Calculate:
(a) The deceleration of the ball.
…………………. m/s2 [2]
(b) Which newton law of motion explains why the ball stops?
…………………………………………………………………………………………………………………………………. [1]
3. A rocket’s engines need to accelerate a 1000 kg rocket vertically upwards at a constant
acceleration of 5 m/s2 . Take acceleration of force of gravity as 9.8 m/s2 .
(a) Draw a free body diagram showing the forces acting on the rocket.
[1]
(b) Calculate the net force that the rocket’s engines need to produce to overcome the
force of gravity and accelerate the rocket at 5 m/s2 .
……………….. N [2]
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Form 3 worksheet 2018
4. When Jane drives to work, she always places her purse on the passenger’s seat. Along
the way she had a sudden stop and her purse has fell on the floor of the car.
(a) Explain what causes the purse to fall from the front seat to the floor?
……………………………………………………………………………………………………………………………
……………………………………………………………………………………………………………………….. [2]
(b) Which newton law of motion explains this?
………………………………………………………………………………………………………………………... [1]
5. (a) Which newton law of motion is also known as Action- reaction?
……………………………………………………………………..……………………………………………………..… [1]
(c) Give an example of a situation that illustrates newton’s law of motion you named
above.
……………………………………………………………………………………………………………………………
………………………………...……………………………………………………………………………………… [1]
6. If you double the force of an object what happens to the acceleration?
……………………………………………………………………………………………………………………………… [1]
7.
If you double the mass of an object what happens to the acceleration?
……………………………………………………………………………………………………………………………… [1]
8. Explain the term inertia?
……………………………………………………………………………………………………………………………………
…………………………………………………………………………………………………………………………….. [1]
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Form 3 worksheet 2018
Module: Machines
Topic: Simple Machines
1. The diagram below shows Thabo and Neo playing on a see- saw. Use it to answer
question 1.
(a) On the diagram clearly label the:
(i) Pivot
(ii) Load when Neo is moving up
[2]
(b) Neo has a mass of 55kg. calculate her weight (g= 10N/kg)
Weight= ……………………………… N [2]
(c) State what Thabo should do to keep Neo up yet applying less effort.
.……………………………………………………………………………………………………… [1]
(d) What is a machine?
………………………………………………………………………………………………………. [1]
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2. Fig. 2.2 shows a support for a leg in plaster and Fig. 2.3 shows a simplified
diagram of the forces acting on the leg.
centre of gravity
hip joint
(pivot)
of leg in plaster
centre of gravity
F
force F
hip joint
34 cm
46 cm
120 N
Fig. 2.2
Fig. 2.3
(a) Calculate the force F needed to keep the leg in a horizontal position.
(b) State the principle of moments.
F = ....................................... [3]
..................................................................................................................................
..................................................................................................................................
................................................................................................................................... [2]
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3. Fig. 6.1 shows a crane lifting some bricks during the building of a house.
arm
counterweight
P
20 m
12000 N
Fig. 6.1
The weight of the bricks produces a turning effect, or moment, on the arm of the crane about
the point P. The weight of the bricks is 12000 N.
(a) Calculate the moment of this force, using the distance marked on Fig. 6.1.
Moment …………………………… [2]
(b) Suggest one advantage of being able to move the counterweight along the arm.
...................................................................................................................................
................................................................................................................................... [2]
(c) Define the term moment.
………………………………………………………………………………………………………………………………
………………………………………………………………………………………………………………………… [1]
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4. The diagram below shows a crane used to lift heavy loads. W is the weight of the
counter weight. Use the diagram to answer question 3.
(a) The crane is in equilibrium.
(b) Calculate the moment of the load about the pivot.
Moment ………………………………….[2]
(c) Calculate force W of the counter weight.
W= ……………………………… N [2]
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5. Fig. 16.1 shows a spanner being used to tighten a nut.
0.15 m
40 N force
nut
spanner
Fig. 16.1
(a) Calculate the moment of the 40 N force about the centre of the nut.
………………………….. [2]
(b) Explain what needs to be changed is the mechanic using the spanner wanted to gain
more mechanical advantage without increasing force applied.
……………………………………………………………………………………………………………………….….. [1]
(c) Which class of levers does the spanner fall in? Explain.
………………………………………………………………………………………………………………………………...
………………………………………………………………………………………………………………………….. [2]
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6. Below are two inclined planes. Use the diagrams to answer questions that follow.
A
B
5m
4m
2m
3m
(a) With calculations of mechanical advantage, Show which of the two ( A and B) inclined
planes would be suitable to use?
………………………………………………….. [2]
(b) At what cost will it be to move the load along A compared to B?
……………………………………………………………………………………………………………………………… [1]
7. If a machine has an effort of 10N and a load of 100N, what is the mechanical advantage of
the machine?
……………………………. [2]
1. .........................................
2. .........................................
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Form 3 worksheet 2018
Module: Body Systems
Topic: Skeletal System
1. Fig. 8.1 shows the bones and muscles of a human leg.
(a) Muscles in the leg work antagonistically.
(i) State which muscle is antagonistic to muscle A.
……………………………………………………………………………………………………………………………………………… [1]
(ii) Explain what is meant by antagonistic
………………………………………………………………….………………………………………………………………………………….
………………………………………………………………….………………………………………………………………………………….
……………………………………………………………..……………………………………………………………………………….. [2]
(b) Label the following:
(i) Bone X: ………………………………………………….
(ii) joint Y: …………………………………………………
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[2]
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2. Fig. 2.1 shows a section through the spinal cord and also some of the muscles and bones of
the arm (not drawn to the same scale).
E........................................
F........................................
Fig. 2.1
(c) On the diagram,
a. label bones E and F;
b. draw in the neurone carrying impulses from the spinal cord to the triceps muscle. [5]
(d) Describe how the structures shown in Fig. 2.1 bring about movement of the arm in the
direction of the arrow.
..........................................................................................................................................
..........................................................................................................................................
..........................................................................................................................................
......................................................................................................................................[3]
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3. Fig. 2.2 shows the legs of an athlete as he starts a race.
G
J
H
I
position 1
position 2
Fig. 2.2
(c) Identify, by letter, two extensor muscles in Fig. 2.2.
1. .........................................
2. .........................................
[2]
(d) Briefly explain how the muscles (G, H, I and J) and the bones brings about movement
for the athlete?
……………………………………………………………………………………………………………………………………
……………………………………………………………………………………………………………………………………
……………………………………………………………………………………………………………………………………
…………………………………………………………………………………………………………………………….. [4]
(e) List the tree main components of the musculoskeletal system.
…………………………………………………….
…………………………………………………….
……………………………………………………..
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[3]
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Form 3 worksheet 2018
4. Damaged joints may be replaced with metal or plastic.
Fig. 1.2 shows a replacement joint in a person’s arm.
KK
Fig. 1.2
(i) Name the type of joint above. ……………………………………………………………………
(v)
[1]
State the type of movement allowed by the joint that has been replaced.
................................................................................................................................. [1]
(vi) There is a structure that attaches a muscle to point K in Fig. 1.2. Name this structure
and explain its importance in the movement of the forearm.
name of structure ......................................................................................................
importance ................................................................................................................
................................................................................................................................... [3]
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5. Diagram 1 shows a bent human arm. Diagram 2 is the cross section of the upper arm
taken through the line X- Y to show the humerus bone and structure L and M.
(a) What type of tissue is L and M.
………………………………………………………………………………………………………. [1]
(b) What actions of structure L and M will make the arm to straighten?
L …………………………………………………………………………………………………………
M …………………………………………………...……………………………………………….. [2]
(c) Name the type of joint at the elbow.
..……………………………………………………………………………………………………... [1]
(d) State the two functions of the human skeleton.
…………………………………………………………………………………………………………
………………………………………………………………………………………………………. [2]
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Form 3 worksheet 2018
Module: Electrical Energy
Topic: Resistance
The diagram below shows a circuit with two bulbs connected in parallel.
Use it to answer question 8.
1. (a) (i) State the reason why the current passing through the bulbs is not equal.
…………………………………………………………………………………………..…………………………………………. (1)
(i)
Given that V = IR, where R is the resistance, I is the current and V is the voltage, calculate
the resistance of bulb F.
………………………………….
(2)
(b) On the diagram, draw the voltmeter measuring the voltage across bulb F.
(2)
(C) The two bulbs are then connected in series.
(iv)
What will happen to the brightness of the bulbs?
…………………………………………………………………………………………………………………………………….……….. (1)
(ii)
Explain your answer in (c) (i).
……………………………………………………………………………………………………………………………… [1]
Use the information and the diagram below to answer question 2.
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The circuit diagram below was used to investigate the electrical resistance of copper and aluminum
metals. A copper wire and an aluminum wire of the same size were placed between points X and Y,
one at a time.
2. a) How many cells are connected in the circuit above?
……………………………………………………………………………………………………………………………. (1)
b) What is meant by electrical resistance?
……………………………………………………………………………………..……………………………………. (1)
c) The below shows the amount of current recorded when each of the two wires were
connected between points X and Y.
Wire
Amount of current/A
Copper
2.58
Aluminum
2.39
i) What conclusion can be drawn from the results?
………………………………………………………………………………………………………………………..
ii)
(1)
State one feature of the wires that could be changed to make the wires to
transmit the same amount of current.
……………………………………………………………………………………………………………………………. (1)
d) State one precaution that should be taken when using electricity.
………………………………………………………………………………………………………………………………………
………………………………………………………………………………………………..……………………………… (1)
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3. Fig. 8.1 shows an electrical circuit using two resistors.
16 V
A
6
S
2
Fig. 8.1
(a)
The switch S is open and the ammeter reading is zero.
State the value of the potential difference across the 6 resistor.
potential difference = ........................................ [1]
(b)
(i)
Switch S is now closed.
State the value of the total resistance of the circuit.
resistance =
(ii)
.............................................[1]
Calculate the current in the ammeter. State clearly the formula that you use.
current = ..................................................
(b) Calculate the potential difference across the 6
resistor.
p.d. = .......................................................
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[2]
[2]
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Use the information and the diagram below to answer questions 4 (a) to (c).
The diagram shows a set-up that was used in an experiment to investigate the relationship
between the length of a wire and its resistance. The voltmeter was used to measure the
potential difference across different lengths of the wire. The sliding contact was initially
placed at the 15 cm mark from the end of the wire.
The experiment was repeated by placing the sliding contact at different lengths of the wire.
Some of the results of the experiment are recorded in the table below.
Length
(cm)
0
15.0
30.0
45.0
60.0
90.0
Voltage
(V)
0
2.0
4.0
6.0
8.0
12.0
Resistance
(Ω)
0
2
4
8
12
4. (a) The current in the circuit was 1.0 A.
The resistance of the wire is calculated using the relationship R=V/I.
Complete the table by calculating the resistance of the wire when the sliding contact was
placed at the 45.0 cm mark.
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Form 3 worksheet 2018
(b) (i) on the grid, plot a graph of resistance against length of the wire.
(4)
(ii) Using your graph, find the resistance when the sliding contact is placed at the 75.0 mark.
Show your working.
………………………………………………………………………………………………………………………..…………… (2)
(c) (i) What conclusion can be drawn from the investigation?
…………………………………………………………………………………………………………………………………………
…………………………………………………………………………………………………………………………………..… (1)
(ii) State one factor which affects the resistance of a wire apart from its length.
…………………………………………………………………………………….………………………………………………. (1)
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5. Fig. 5.1 shows an electrical circuit.
lamp
X
200 Ω
Fig. 5.1
(a) State the name of component X.
......................................................................................................................................
[1]
6. Fig. 5.2 shows the graph of current against potential difference for the lamp.
0.07
current/A
0.06
0.05
0.04
0.03
0.02
0.01
0.000
1
2
3
4
5
potential difference/V
Fig. 5.2
6
The potential difference across the lamp is 2.5 V. Determine
(iv)
the current in the lamp,
current = ......................................
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(ii) the current in the 200 Ω resistor,
current = ......................................
(iii)
the current in component X.
current = ......................................
7. Fig. 6.1 shows a circuit in which a voltmeter is placed across a resistor.
B
18 Ω
power
supply
12 Ω
V
A
Fig. 6.1
The potential difference across the 12 Ω resistor is 4.0 V.
The voltmeter has three different ranges: 0 to 3.0 V, 0 to 6.0 V and 0 to 30 V. The best range for
use in this circuit is 0 to 6.0 V.
(a)
(i)
Explain why
using the voltmeter on the range 0 to 3.0 V is unsuitable,
................................................................................................................................................................................
......................................................................................................................................................................... [1]
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Form 3 worksheet 2018
(ii)
using the voltmeter on the range 0 to 30 V is unsuitable.
................................................................................................................................................................................
......................................................................................................................................................................... [1]
9. (i) Calculate the current in the 12 Ω resistor. State the formula that you use.
………………………………………. [2]
(ii)Calculate potential between A and B in figure 6.1.
…………………………………… [2]
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8. Fig. 7.1 shows an electrical circuit containing a 12 V power supply and a number of
resistors.
12 V
6Ω
A
3Ω
2Ω
4Ω
Fig. 7.1
(a) Calculate the combined resistance of
(i) the 2 Ω and 4 Ω resistors in series,
(ii)
resistance = ................................................
[1]
resistance = ................................................
[2]
the 3 Ω and 6 Ω resistors in parallel.
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(b)
Calculate the reading of the ammeter in Fig. 7.1.
ammeter reading = ................................................
(c)
[2]
Determine the potential difference across the 4 Ω resistor.
p.d. = ................................................
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9. The diagram below shows an electric circuit.
(a) What does instrument P measure?
...………………………………………………………………………………………………… [1]
(b) How many cells make up the battery in the circuit?
...………………………………………………………………………………………………… [1]
(c) The jockey can be placed at either of the points A, B, or C.
(i) At which of the points would the resistance of the circuit be highest?
……………...………………………………………………………………………………. [1]
(ii) Explain your answer in (c) (i).
………...……………………………………………………………………………………. [1]
(d) State the relationship between the resistance of a conductor and its cross- sectional
area.
...………………………………………………………………………………………………… [1]
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