Unit Test
Academic Year 2024-2025, Semester 2
General Science - Year 8
January 2025
Topic: Reactivity
50 minutes
/ 40 Marks
Answer questions on the space provided in the exam paper or on extra paper if the
question asks for you to. Ask the invigilator for rough work papers if needed.
READ THESE INSTRUCTIONS FIRST
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•
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Write in dark blue or black ink.
You may use a soft pencil for any diagrams, graphs or rough working.
Do not use staples, paper clips, highlighters, glue or correction fluid.
Answer all questions.
The number of marks is given in brackets [ ] at the end of each question or part question.
STUDENT NAME
: ________________________
DATE
: ________________________
Section A
/10
Section B
/20
SCORE
SECTION A (MULTIPLE CHOICE QUESTIONS)
1
What kind of gas that given out during the reaction between sodium and water?
A
Hydroxide
B
Hydrogen
C
Oxygen
D
Carbon dioxide
[1]
2
The list shows the name of five metals in order from the most to the least reactive.
Zinc
Iron
Tin
Copper
Silver
Which of the following metals can displace the rest from their salt solutions?
A
Silver
B
Zinc
C
Iron
D
Copper
[1]
3
Three solutions are given and labeled as A, B, and C. Aleksa then conducted a simple
experiment to test the order of reactivity between those solutions. Based on his
observations,
(1) where solution A is added to solution B, it changes colour.
(2) where solution C is added to solution B, it does not change colour.
What can be concluded about reactivity of A, B and C?
A
A>C>B
B
C>A>B
C
A>B>C
D
C>B>A
[1]
4
An iron nail is dipped into a beaker which containing copper sulphate solution, illustrated in
the picture below.
Which of the following is true about the reaction that happened?
A
The solution changes colour to blue
C The solution volume increases
B
Iron nail dissolves completely
D Iron nail becomes brownish in colour
[1]
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5
Klara are being told by her teacher to store copper sulfate solution inside a container that
made from metal. If the container that is used should be able to maintain the solution so it
could last long, what kind of metal container that Klara could use?
A
Silver
B Tin
C
Zinc
D Iron
[1]
6
Renji currently making copper chloride as an experiment for his laboratory assignment.
Which of the following that shows the complete equation of Renji experiment?
A Copper + hydrochloric acid → copper chloride + water
B Copper + sulfuric acid → copper chloride + water
C Copper + hydrochloric acid → copper chloride + hydrogen
D Copper + hydrochloric acid → copper chloride + carbon dioxide
[1]
7
Following table represents the type of reactions of three metals with various solutions.
Which represents the correct order of reactivity of metals A, B and C?
A
C>A>B
B
A>C>B
C
A>B>C
D
C>B>A
[1]
8
The list shows the method that used to make copper sulfate salts.
(1) Copper oxide powder is added to the acid.
(2) The excess copper oxide is removed by filtering.
(3) The solution is heated until the first crystals appear.
(4) The solution is put into an evaporating dish.
(5) The solution is left for a few days until the copper sulfate salt completely formed.
Which of the process that happened during step number (4) that contributed to form the
salt?
A Evaporation
B Sublimation
C Condensation
D Crystallization
[1]
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9
Review this particular step from the copper sulfate salt making method:
(1) Copper oxide powder is added to the acid.
What kind of acid is used at that step?
A
Hydrochloric acid
C Nitric acid
B
Sulfuric acid
D Carbonic acid
[1]
10 Two reactants are given to form a salt.
magnesium carbonate + nitric acid
What will be the possible result of those reactants?
A Magnesium will replace hydrogen to form magnesium nitrate
B Magnesium will replace nitrate to form magnesium hydroxide
C Magnesium will remain paired with carbonate and no reaction occurred
D Magnesium will remain paired with hydrogen
[1]
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SECTION B (THEORY)
1
Complete the word equation.
a)
+ oxygen → magnesium oxide
b) Sodium +
[1]
→ sodium hydroxide + hydrogen
c)
+ water →
[1]
+ hydrogen
[2]
[Total: 4]
2
An experiment was set up to investigate rusting.
a) Rust is an oxide of iron.
Write a word equation for the formation of iron oxide from its elements.
…………………………………………………………………………………………………………………………………….... [1]
b) Circle one of the following words that describe the formation of iron oxide.
combustion
condensation
decomposition
oxidation
[1]
[Total: 2]
3
Railway lines can be joined together by pouring molten iron into the gap between them.
a) The molten iron is produced by the reaction between powdered aluminium and iron
oxide.
Complete the word equation for the reaction.
aluminium + iron oxide → iron + .....................................
[1]
b) Iron can be produced from a mixture of aluminium and iron oxide but not from a
mixture of copper and iron oxide.
Write the names of the three metals, in the order of their reactivity.
most reactive
…………………………………….
…………………………………….
…………………………………….
[1]
[Total: 2]
4
Complete these sentences about making salts.
Choose words from the list.
hydrogen
water
carbon atom
carbon dioxide
oxygen
oxide ion
Salts can be made by reacting metals or metal carbonates with acid.
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When metals react with acid, the products are a salt and ……………………….
When metal carbonates react with acid, the products are a salt, …………………….…. and
…………………………… .
[Total: 3]
5
The list shows the names and symbols of five metals in order of their reactivity.
a) What, if anything, would be the result of heating calcium powder with zinc oxide?
…………………………………………………………………………………………………………………………………….... [2]
b) Write down the name of a metal in the list that will not react with a solution of
magnesium sulphate.
……………………………………………………………………………………………………………………………..……….. [2]
c) In his experiment, Aleksa added a spoon of calcium powder to a beaker containing
sodium chloride solution. He waited for minutes and even heated the solution, but no
change observed.
Explain the reason why.
…………………………………………………………………………………………………………………………………..…..
………………………………………………………………………………………………………………………………………
…………………………………………………………………………………………………………………………………..….. [3]
d) In the table below, write the name of the compound represented by each formula.
[2]
[Total: 9]
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6
Annisa investigates a type of reaction.
She reacts different metals with different salt solutions.
Here are her results.
a) What type of reaction does Annisa investigate?
………………………………………………………………………………………………………………………….……..
[1]
b) Put the metals in order of reactivity.
One has been done for you.
most reactive
…………………………………….
…………………………………….
iron
…………………………………….
least reactive
…………………………………….
[3]
c) Magnesium reacts with zinc sulfate solution.
This reaction has two products.
Write the word equation for this reaction.
[Total: 6]
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7
Marcia sets up the following experiment.
Each container has hydrochloric acid in it along with a metal.
1 – magnesium
2 – copper
3 – zinc
4 – iron
5 – aluminium
a) What kind of reaction product that caused the bubbles in the container?
……………………………………………………………………………………………………………………………………… [1]
b) Choose any reaction from one container only and write the complete word equation.
Test tube no. ….
…….………….……
+ ……………..……… → ………….…….… + …….……….….…
[2]
c) Marcia takes another container that also filled with hydrochloric acid, then put a copper
plate inside.
Choose name represents a salt that will be formed in this new container by circling it.
copper carbonate
magnesium carbonate
magnesium chloride
copper chloride
[1]
[Total: 4]
END OF THE PAPER
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