Christian & Missionary Alliance Sun Kei Secondary School
2019 – 2020 S.3 Chemistry
Homework - Metal Reactivity Series
26 )
Anthony Li
Name: _________________(
Date of Submission: 20-2-2020
I
Class：S.3_____
1.
A student performs several experiments to determine the order of reactivity of four metals. The
results are shown in the table below.
Metal
Experiment
W
X
Y
Z
Reaction with
cold water
reacts readily
no observable
change
no observable
change
reacts
vigorously
Reaction with
dilute
reacts readily
reacts very
slowly
reacts slowly
very dangerous
NEVER
hydrochloric
acid
attempt
(a) Arrange the metals in order of reactivity, starting with the most reactive one. Explain
your answer briefly.
(4 marks)
z
w
Y
X
Reactivity: __________
> __________
> __________
> __________
Explanation:
___Z____
is
more
reactive
than
__W_____
because
___Z____
reacts
with
___cold water vigorously____________ but __W reacts readily_______________.
W
_______
is
more
reactive
than
Y
_______
because
W
_______
reacts
with
diluted hydrochloric acid fastly
react with Y slowly
___________________________________
but ___________________________________.
Y
_______
is
more
reactive
than
X
_______
because
Y
_______
reacts
with
diluted hydrochloric acid slower
the reaction of X is very slow
___________________________________
but ___________________________________.
(b) Metal W reacts with oxygen to give a brick-red flame.
(i) Suggest what metal W might be.
W:
(1 mark)
Calcium
(ii) Write a word equation for the reaction between W and water.
metal W+ Water
(1 mark)
metal W hydrochloric + hydrogen
1920 S3 Chemistry Homework (Metal Reactivity Series)
1
2.
The reactivity of metals can be determined by the reaction between metal and acid.
Five different metals, calcium, tin, zinc, copper and nickel are added to dilute hydrochloric
acid respectively. The gas produced is collected by displacement of water. The height of gas
collected in the first 30 seconds in each case is measured.
The results are shown in the following table.
Metal
Height (cm) of gas collected in the first 30
seconds
Calcium
5.5
Tin
1
Zinc
4.5
Copper
0
Nickel
2.5
(a) Write a word equation for the reaction between zinc and dilute hydrochloric acid.
(1 mark)
zinc + hydrochloric acid
zinc chloride + hydrogen
(b) Suggest a test for the gas evolved.
(1 mark)
put the lighting split into the gas to test
(c) Determine the reactivity series in descending order from the results provided.
(1 mark)
Ca>zinc>Nickel>Tin>Copper
(d) Explain why the reactivity of sodium CANNOT be determined by this method.
(1 mark)
because sodium will be explosed with diluted hydrochloric acid.
1920 S3 Chemistry Homework (Metal Reactivity Series)
2
2.
(e) Another metal was tested and the result was as follows:
(i)
Metal
Height (cm) of gas collected
in the first 30 seconds
X
5
From the result obtained, rewrite the reactivity series in descending order.
(1 mark)
Ca>X>Zinc>Nickel>Tin>Mg>copper
(ii) Suggest what metal X might be.
X: Magnesium
(1 mark)
3.
X, Y and Z are three different metals. The table below lists the results of three experiments
carried out using the metals.
Experiment
X
Y
Z
Adding metal to
cold water
no observable
change
no observable
change
reacts vigorously
Adding metal to
dilute hydrochloric
acid
reacts readily
no observable
change
reacts vigorously
Burns in air
Bright white light
no observable
change
reacts vigorously
(a) Arrange the three metals in order of increasing reactivity. Explain your answer. (Please use
the sentence pattern of Q1(a).)
(3 marks)
Z>X>Y
Z is more reactive than X because Z reacts vigorously with lot of hydrochloric acid but X
reacts readily.X is more reactive than Y because X reacts with diluted hydrochloric acid
readily but Y do not have any observation
(b) Suggest what X, Y and Z might be.
(3 marks)
X: calcium
Y: gold
Z: potassium
1920 S3 Chemistry Homework (Metal Reactivity Series)
3
4.
Answer the following multiple-choice questions.
(a) Which of the following is INCORRECT when some sodium granules are put into cold
water?
A The metal floats on water surface.
B An alkaline solution is formed.
C The metal moves very rapidly.
D The metal burns with a brick-red flame.
D
Answer: _______
(b) Which of the following combinations describing the reaction between potassium and
water is correct?
Resultant solution
Gas evolved
A
Acidic
Oxygen
B
Alkaline
Oxygen
C
Acidic
Hydrogen
D
Alkaline
Hydrogen
D
Answer: _______
(c) Which of the following flame colours does NOT match correctly?
Metal
Flame colour
A
Magnesium
White
B
Calcium
Brick-red
C
Sodium
Blue
D
Potassium
Lilac
B
Answer: _______
(d) In school laboratory, hydrogen gas can be safely produced by adding dilute hydrochloric acid
to
A copper.
B sodium.
C magnesium.
D potassium.
C
Answer: _______
(e) Which of the following metals will NOT form oxide(s) when heated strongly in air?
(1) Calcium
(2) Platinum
(3) Sodium
A (1) only
B (2) only
C (1) and (3) only
D (2) and (3) only
C
Answer: _______
1920 S3 Chemistry Homework (Metal Reactivity Series)
4