Cambridge Lower Secondary Checkpoint
*4657240416*
SCIENCE
0893/01
Paper 1
October 2023
45 minutes
You must answer on the question paper.
No additional materials are needed.
INSTRUCTIONS
• Answer all questions.
• Use a black or dark blue pen. You may use an HB pencil for any diagrams or graphs.
• Write your name, centre number and candidate number in the boxes at the top of the page.
• Write your answer to each question in the space provided.
• Do not use an erasable pen or correction fluid.
• Do not write on any bar codes.
• You should show all your working in the booklet.
• You may use a calculator.
INFORMATION
• The total mark for this paper is 50.
• The number of marks for each question or part question is shown in brackets [ ].
This document has 20 pages. Any blank pages are indicated.
B23 10_0893_01/8RP
© UCLES 2023
[Turn over
1/72
2
1
The arrows show the pathway of water through the root.
A
water
enters
the cell
B
soil particle
(a) Name the type of root cell labelled A.
[1]
(b) Suggest one way root cell A is adapted to its function.
Use the diagram to help you.
[1]
(c) Water is transported from the roots to the stem and the leaves through vessel B.
Name vessel B.
[1]
(d) Vessel B transports minerals to the leaves.
Name the mineral needed to make chlorophyll.
[1]
© UCLES 2023
0893/01/O/N/23
2/72
3
2
Safia has a solution of copper sulfate.
Describe how Safia makes large and dry copper sulfate crystals from this solution.
Use labelled diagrams to help you with your description.
[3]
© UCLES 2023
0893/01/O/N/23
3/72
[Turn over
4
3
Heat and temperature are different.
(a) Tick (✓) all the correct statements that describe heat.
a measure of how cold something is
a measure of how hot something is
a measure of the thermal energy of a substance
measured in MJ
transferred by conduction
[2]
(b) Measurements of temperature in °C can be positive, negative or zero.
Describe how the temperature measurements of water can be positive, negative or zero.
Use ideas about the three states of matter in your answer.
[2]
© UCLES 2023
0893/01/O/N/23
4/72
5
4
This question is about the carbon cycle and climate change.
(a) Complete the carbon cycle diagram.
Choose words from the list.
combustion
decomposition
photosynthesis
feeding
respiration
sunlight
carbon dioxide in
the atmosphere
..........................................................
..........................................................
..........................................................
fossil
fuel
power
station
..........................................................
..........................................................
dead plants
and animals
fossil fuels
NOT TO SCALE
[3]
(b) Describe what happens during decomposition.
[1]
(c) The main cause of climate change is burning fossil fuels.
Describe one effect of climate change.
[1]
© UCLES 2023
0893/01/O/N/23
5/72
[Turn over
6
5
Mia and Aiko are discussing ideas about fetal development and the health of the mother.
A scientific study has shown that the mass
of an unborn baby will be less if the mother
has an unhealthy diet.
So, I think the mother should be careful
what she eats.
Mia
My mother says she ate what she
wanted and I was born healthy.
So, I don’t think it matters what
the mother eats.
Aiko
(a) Who has made a more informed decision?
Tick (✓) one box.
Mia
Aiko
Explain your answer.
[1]
(b) The diet of the mother is one factor that affects fetal development.
Write down one other factor that affects fetal development.
[1]
© UCLES 2023
0893/01/O/N/23
6/72
7
6
Many scientists believe that a large asteroid collided with the Earth over 65 million years ago.
(a) Two effects of this collision were the formation of a crater and climate change.
Write down one other possible effect of this collision.
[1]
(b) Carlos models an asteroid colliding with the Earth.
He drops a steel ball into a box containing sand.
steel ball
sand
crater
before
after
(i) Describe what the steel ball and the sand represent in his model.
steel ball
sand
[2]
(ii) Suggest two ways Carlos increases the width and depth of the crater.
1
2
[2]
© UCLES 2023
0893/01/O/N/23
7/72
[Turn over
8
7
Waveforms show how sound waves interact.
Look at the different waveforms.
A
B
C
D
(a) Waveform B is the result of the interaction between two waveforms.
Which word describes this interaction?
[1]
(b) Look at this diagram showing two waveforms.
Which waveform A, B, C or D is the result of the interaction between these two waveforms?
[1]
(c) Look at this diagram showing two waveforms.
Which waveform A, B, C or D is the result of the interaction between these two waveforms?
[1]
© UCLES 2023
0893/01/O/N/23
8/72
9
8
(a) Chen investigates the inheritance of sex in humans.
Chen:
• uses green balls to represent gametes with X chromosomes
• uses yellow balls to represent gametes with Y chromosomes
• puts 25 green balls and 25 yellow balls into bag A
• puts 50 green balls into bag B
• takes one ball out of each bag and records the colours
• returns the balls to their bags.
Explain why bag A represents male gametes.
[1]
(b) Chen takes balls out of the bags five more times.
(i) Look at the table of his results.
The table is not complete.
Complete the table to identify if the two balls (gametes) chosen represent a male or a
female offspring.
colour of ball from
bag A
colour of ball from
bag B
1
green
green
2
yellow
green
3
green
green
4
yellow
green
5
green
green
6
green
green
male or female
offspring
[1]
(ii) The chance of a male and a female producing a male offspring is 50%.
Chen’s results do not show a value of 50%.
Suggest why.
[1]
© UCLES 2023
0893/01/O/N/23
9/72
[Turn over
10
9
Sodium is in Group 1 of the Periodic Table.
Sodium reacts with chlorine to form an ionic compound.
This ionic compound contains sodium ions, Na+, and chloride ions, Cl –.
Why is a sodium ion positively charged?
Circle the correct answer.
a sodium atom gains a proton
a sodium atom loses a proton
a sodium atom gains an electron
a sodium atom loses an electron
[1]
© UCLES 2023
0893/01/O/N/23
10/72
11
10 The albatross is a sea bird with very long wings.
(a) The albatross may have long wings due to the process of natural selection.
Tick (✓) all the boxes that show correct statements about natural selection and the
albatross.
The albatross with longer wings pass on their genes to their offspring.
There is no variation in the length of albatross wings.
The albatross do not compete for food.
The length of the wings decreased over many generations.
The albatross with longer wings are more likely to survive.
[2]
© UCLES 2023
0893/01/O/N/23
11/72
[Turn over
12
(b) A scientist counts the number of albatross that nest on an island every year.
Look at the results.
2000
1800
1600
number of
albatross
1400
1200
1000
800
600
1980
1990
2000
year
2010
2020
Complete these sentences.
Between the years 1980 and 2020, the number of albatross
One reason for this could be
.
.
If the trend in the graph continues, the albatross species could become
.
[3]
© UCLES 2023
0893/01/O/N/23
12/72
13
11 Rajiv investigates the reaction of zinc, Zn, and dilute sulfuric acid, H2SO4.
Hydrogen, H2, and zinc sulfate, ZnSO4, are made in the reaction.
(a) Write the symbol equation for this reaction.
+
.................................
+
.................................
.................................
.................................
[2]
(b) Rajiv:
• puts 25 cm3 of dilute sulfuric acid into a flask
• adds 0.50 g (an excess) of zinc powder to the sulfuric acid
• assembles the equipment shown in the diagram
20
40
60
80 100 cm3
gas syringe
flask
25 cm3 of dilute sulfuric acid
0.50 g (an excess) of zinc powder
• measures the total volume of hydrogen collected in the gas syringe every 10 seconds.
© UCLES 2023
0893/01/O/N/23
13/72
[Turn over
14
(i) Look at the graph showing his results.
80
60
total volume
of hydrogen
collected 40
in cm3
20
0
0
10
20
30
40 50
time in s
60
70
80
Rajiv repeats the experiment using the same quantities of zinc powder and dilute sulfuric
acid.
He uses acid at a higher temperature.
He does not change any other conditions.
Sketch a line on the graph to show the results of this experiment.
Label the line H.
[2]
(ii) Rajiv repeats the experiment a second time using the same quantities of zinc and dilute
sulfuric acid.
He uses a lump of zinc instead of zinc powder.
He does not change any other conditions.
The rate of the reaction decreases.
Explain why.
Use ideas about the particle model.
[2]
© UCLES 2023
0893/01/O/N/23
14/72
15
12 Blessy investigates floating and sinking.
She puts a whole lemon in a beaker of water.
lemon
water
The whole lemon floats.
Water has a density of 997 kg / m3.
Whole lemon has a density of 984 kg / m3.
Look at the table showing the density of different parts of a lemon.
part of lemon
density
in kg / m3
peel
956
segment
998
seed
925
(a) Predict which parts of the lemon float when in water.
Explain your answer.
[1]
© UCLES 2023
0893/01/O/N/23
15/72
[Turn over
16
(b) Blessy wants to find out if the different parts of a lemon will float or sink in salt solution.
She predicts that as the concentration of salt solution increases eventually all three parts of
the lemon will float.
Write a plan for her investigation.
[2]
© UCLES 2023
0893/01/O/N/23
16/72
17
13 Elements and compounds either have a giant structure or a simple structure.
The table shows information about five substances.
Complete the table to identify if the structure of each substance is giant or simple.
substance
melting point
boiling point
does it conduct
electricity
J
low
low
no
K
high
high
yes
L
low
low
no
M
high
high
no
N
high
high
no
structure
(giant or simple)
[2]
© UCLES 2023
0893/01/O/N/23
17/72
[Turn over
18
14 Ahmed describes an electrical circuit.
My circuit is a complete series circuit with:
• one battery of cells
• two lamps
• one open switch
• one variable resistor
• one meter to measure the current in the whole circuit
• one meter to measure the voltage across the variable resistor.
Draw his circuit using conventional symbols.
The battery of cells has been drawn for you.
[4]
© UCLES 2023
0893/01/O/N/23
18/72
© UCLES 2023
21
22
0893/01/O/N/23
19/72
40
38
Sr
strontium
88
56
Ba
barium
137
88
39
37
Rb
rubidium
85
55
Cs
caesium
133
87
actinoids
lanthanoids
–
calcium
potassium
–
actinoids
Ca
K
Ra
20
19
radium
89–103
24
23
Fr
104
57–71
magnesium
sodium
francium
178
89
Mg
Na
name
cerium
140
90
Th
thorium
232
lanthanum
139
89
Ac
actinium
–
231
protactinium
Pa
91
141
praseodymium
Pr
59
58
Ce
57
–
–
dubnium
Db
105
181
tantalum
Ta
73
93
niobium
Nb
41
51
vanadium
V
23
Cr
24
238
uranium
U
92
144
neodymium
Nd
60
–
seaborgium
Sg
106
184
tungsten
W
74
96
molybdenum
Mo
42
52
chromium
relative atomic mass
rutherfordium
Rf
hafnium
Hf
72
91
zirconium
Zr
40
48
titanium
La
lanthanoids
yttrium
Y
39
45
scandium
Ti
12
11
Sc
9
7
atomic symbol
Be
beryllium
Li
lithium
atomic number
4
3
Key
2
1
–
neptunium
Np
93
–
promethium
Pm
61
–
bohrium
Bh
107
186
rhenium
Re
75
–
technetium
Tc
43
55
manganese
Mn
25
–
plutonium
Pu
94
150
samarium
Sm
62
–
hassium
Hs
108
190
osmium
Os
76
101
ruthenium
Ru
44
56
iron
Fe
26
27
28
29
30
–
americium
Am
95
152
europium
Eu
63
–
meitnerium
Mt
109
192
–
curium
Cm
96
157
gadolinium
Gd
64
–
darmstadtium
Ds
110
195
platinum
Pt
Ir
iridium
78
106
palladium
Pd
46
59
nickel
Ni
77
103
rhodium
Rh
45
59
cobalt
Co
–
berkelium
Bk
97
159
terbium
Tb
65
–
roentgenium
Rg
111
197
gold
Au
79
108
silver
Ag
47
64
copper
Cu
–
californium
Cf
98
163
dysprosium
Dy
66
–
copernicium
Cn
112
201
mercury
Hg
80
112
cadmium
Cd
48
65
zinc
Zn
B
C
–
einsteinium
Es
99
165
holmium
Ho
67
–
nihonium
Nh
113
204
thallium
Tl
81
115
–
fermium
Fm
100
167
erbium
Er
68
–
flerovium
Fl
114
207
lead
Pb
82
119
tin
Sn
In
indium
50
73
germanium
Ge
32
28
silicon
Si
14
12
carbon
49
70
gallium
Ga
31
27
aluminium
Al
13
11
boron
6
–
mendelevium
Md
101
169
thulium
Tm
69
–
moscovium
Mc
115
209
bismuth
Bi
83
122
antimony
Sb
51
75
arsenic
As
33
31
phosphorus
P
15
14
nitrogen
N
7
–
nobelium
No
102
173
ytterbium
Yb
70
–
livermorium
Lv
116
–
polonium
Po
84
128
tellurium
Te
52
79
selenium
Se
34
32
sulfur
S
16
16
oxygen
O
8
–
lawrencium
Lr
103
175
lutetium
Lu
71
–
tennessine
Ts
117
–
astatine
At
85
127
iodine
I
53
80
bromine
Br
35
35.5
chlorine
Cl
17
19
fluorine
F
9
–
oganesson
Og
118
–
radon
Rn
86
131
xenon
Xe
54
84
krypton
Kr
36
40
argon
Ar
18
20
neon
Ne
10
4
5
helium
8
1
7
hydrogen
6
2
5
He
4
H
3
1
Group
The Periodic Table of Elements
20
Cambridge Lower Secondary Checkpoint

SCIENCE
0893/02
Paper 2
October 2023
45 minutes
You must answer on the question paper.
No additional materials are needed.
INSTRUCTIONS
• Answer all questions.
• Use a black or dark blue pen. You may use an HB pencil for any diagrams or graphs.
• Write your name, centre number and candidate number in the boxes at the top of the page.
• Write your answer to each question in the space provided.
• Do not use an erasable pen or correction fluid.
• Do not write on any bar codes.
• You should show all your working in the booklet.
• You may use a calculator.
INFORMATION
• The total mark for this paper is 50.
• The number of marks for each question or part question is shown in brackets [ ].
This document has 16 pages.
IB23 10_0893_02/9RP
© UCLES 2023
[Turn over
20/72
2
1
The diagram shows the position of some organs in the human body.
A
D
B
C
(a) Circle the letter of the organ that is part of the human excretory (renal) system.
A
B
C
D
[1]
(b) Complete these sentences about the human excretory (renal) system.
The function of the human excretory (renal) system is to
the
blood to remove urea.
The urea is then excreted in a liquid called
.
[2]
(c) Organs are made of cells.
Cells contain chromosomes.
Name the chemical from which chromosomes are made.
[1]
© UCLES 2023
0893/02/O/N/23
21/72
3
2
Look at the elements in Group 1 from the Periodic Table.
The elements are in the same order as the Periodic Table.
element
lithium
sodium
potassium
rubidium
caesium
francium
(a) Describe how the melting points of the Group 1 elements change down the group.
[1]
(b) Name the most reactive element in Group 1.
[1]
(c) An element in Group 1 reacts with dilute hydrochloric acid.
Circle the gas made in this reaction.
carbon dioxide
chlorine
hydrogen
oxygen
[1]
© UCLES 2023
0893/02/O/N/23
22/72
[Turn over
4
3
Mike holds a metal cup containing water.
hand A
metal cup
containing water
hand B
(a) The water in the metal cup is at a higher temperature than both of his hands.
Describe what happens to the thermal energy in the water.
[1]
(b) Mike pours the water out of the metal cup.
He adds ice and water to the metal cup.
Describe what Mike feels with hand B compared to hand A.
[1]
4
The atoms in a molecule of water are joined together by covalent bonds.
(a) What is a covalent bond?
[2]
(b) The formula for a molecule of ethane is C2H6.
How many atoms are bonded together in one molecule of ethane?
[1]
© UCLES 2023
0893/02/O/N/23
23/72
5
5
Priya compares different sound waveforms.
All the waveforms are drawn to the same scale.
A
B
C
D
(a) Which two waveforms have the lowest amplitude?
and
[1]
(b) Which two waveforms have the lowest frequency?
and
[1]
(c) Which two waveforms have the highest pitch?
and
[1]
(d) Draw a waveform on the grid with a greater loudness than waveform E.
E
[1]
© UCLES 2023
0893/02/O/N/23
24/72
[Turn over
6
6
Look at the food web for a habitat.
lion
jackal
wild cat
rabbit
owl
small
rodents
green plant
NOT TO SCALE
(a) A disease decreases the number of small rodents in the habitat.
The number of owls decreases but the number of wild cats stays the same.
Complete the sentences to explain why.
The number of owls decreases because
.
The number of wild cats stays the same because
.
[2]
(b) Explain why green plants need the Sun to survive.
[3]
© UCLES 2023
0893/02/O/N/23
25/72
7
7
An object has volume, mass and density.
The object has a volume of 28 cm3.
The mass of the object is 222 g.
Calculate the density of the object.
g / cm3
8
[2]
The diagram shows part of the Periodic Table.
1
H
2
He
3
Li
4
Be
5
B
6
C
7
N
8
O
9
F
10
Ne
11
Na
12
Mg
13
Al
14
Si
15
P
16
S
17
Cl
18
Ar
19
K
20
Ca
(a) Which element in the table has the lowest number of protons in its atom?
[1]
(b) Identify two elements from the table that are in the same period as the element Mg.
and
[1]
(c) Name one element from the table that has the same chemical properties as the element Ar.
[1]
© UCLES 2023
0893/02/O/N/23
26/72
[Turn over
8
9
Mia is learning about tectonic plates.
She knows that:
• diverging tectonic plates move away from each other
• converging tectonic plates move towards each other.
(a) Label the diagram.
Choose words from the list.
diverging plates
convection currents
crust
converging plates
mantle
...........................................
...........................................
...........................................
...........................................
...........................................
...........................................
...........................................
...........................................
...........................................
...........................................
[2]
© UCLES 2023
0893/02/O/N/23
27/72
9
(b) Mia joins a map of South America to Africa.
South
America
Africa
Explain why the appearance of the continental coasts is evidence for tectonic plates.
[2]
(c) Write down one other piece of evidence for tectonic plates.
[1]
© UCLES 2023
0893/02/O/N/23
28/72
[Turn over
10
10 Oliver connects a resistor in an electrical circuit.
He measures the current as he increases the voltage across the resistor.
Oliver draws a graph.
3
2
current in A
1
0
0
1
2
3
voltage in V
4
5
(a) Current is measured in A (amps) and voltage is measured in V (volts).
Write down the unit of resistance.
[1]
(b) Calculate the resistance of the resistor.
Include the equation used to calculate resistance in your answer.
resistance =
© UCLES 2023
0893/02/O/N/23
29/72
[2]
11
11 Scientists believe that the Moon was formed after a collision between the Earth and another
small planet.
This is called the collision theory for the formation of the Moon.
debris
Earth
small planet
The debris from the collision collected to form the Moon.
(a) Chen collects information about the elements found on the Earth and on the Moon.
element
percentage of element found on the
Earth
Moon
oxygen
45.3
44.7
silicon
22.0
22.5
magnesium
2.6
2.3
iron
6.0
8.3
calcium
3.6
3.1
(i) Most of the information supports the collision theory.
Explain how most of this information supports the collision theory.
[1]
(ii) There is a comparison of one element that does not support the collision theory.
Write down the name of this element.
[1]
(b) Suggest two other pieces of evidence Chen collects to support the collision theory.
1
2
[2]
© UCLES 2023
0893/02/O/N/23
30/72
[Turn over
12
12 Theories about the structure of the atom have developed over time.
Look at the models of an atom of nitrogen.
model A in 1904
–
–
model B in 1914
electron
–
–
+
–
–
–
–
–
–
–
nucleus
–
–
–
(a) Describe one similarity between model A and model B.
[1]
(b) Describe one difference between model A and model B.
[1]
(c) Model B is still used today.
Suggest one strength and one limitation of using model B.
strength
limitation
[2]
© UCLES 2023
0893/02/O/N/23
31/72
13
13 Yuri investigates convection.
He adds a drop of red ink to the cold water as shown in the diagram.
red ink
cold water
very
hot
water
(a) Complete the sentence to suggest a testable hypothesis for this investigation.
I predict that the red ink will move
because
.
[1]
(b) Complete the table about safety risks and the control of risks in this investigation.
safety risk
control of risk
very hot water may burn skin
………………………….………….
………………………….………….
………………………….………….
red ink may irritate skin
………………………….………….
………………………….………….
use plastic beaker instead of glass beaker
………………………….………….
[3]
© UCLES 2023
0893/02/O/N/23
32/72
[Turn over
14
14 Lily investigates variation in tomatoes.
Lily:
•
measures the mass of different tomatoes to the nearest whole gram
•
classifies the tomatoes into different groups based on their masses.
Lily writes about her results.
There were 3 tomatoes with a mass more than 105 g.
There were 2 tomatoes with a mass between 76 g and 80 g.
There were 6 tomatoes with a mass between 101 g and 105 g.
There were 8 tomatoes with a mass between 86 g and 90 g.
There were 9 tomatoes with a mass between 91 g and 95 g.
There were 12 tomatoes with a mass between 96 g and 100 g.
There were 4 tomatoes with a mass between 81 g and 85 g.
(a) (i) Complete the table of results by writing the:
• unit for the mass range
• number of tomatoes in each mass range.
mass range
number of tomatoes
in ………………….
in mass range
76 – 80
………………….
81 – 85
………………….
86 – 90
………………….
91 – 95
………………….
96 – 100
………………….
101 – 105
………………….
more than 105
………………….
[2]
© UCLES 2023
0893/02/O/N/23
33/72
15
(ii) What is the best way to present the data in the table?
[1]
(b) Gardeners add nitrates to the soil to help tomato plants grow.
The nitrates are used by the plants to make a substance needed for growth.
Name this type of substance.
[1]
Permission to reproduce items where third-party owned material protected by copyright is included has been sought and cleared where possible. Every
reasonable effort has been made by the publisher (UCLES) to trace copyright holders, but if any items requiring clearance have unwittingly been included, the
publisher will be pleased to make amends at the earliest possible opportunity.
To avoid the issue of disclosure of answer-related information to candidates, all copyright acknowledgements are reproduced online in the Cambridge
Assessment International Education Copyright Acknowledgements Booklet. This is produced for each series of examinations and is freely available to download
at www.cambridgeinternational.org after the live examination series.
Cambridge Assessment International Education is part of Cambridge Assessment. Cambridge Assessment is the brand name of the University of Cambridge
Local Examinations Syndicate (UCLES), which is a department of the University of Cambridge.
© UCLES 2023
0893/02/O/N/23
34/72
[Turn over
© UCLES 2023
21
22
0893/02/O/N/23
35/72
40
38
Sr
strontium
88
56
Ba
barium
137
88
39
37
Rb
rubidium
85
55
Cs
caesium
133
87
actinoids
lanthanoids
–
calcium
potassium
–
actinoids
Ca
K
Ra
20
19
radium
89–103
24
23
Fr
104
57–71
magnesium
sodium
francium
178
89
Mg
Na
name
cerium
140
90
Th
thorium
232
lanthanum
139
89
Ac
actinium
–
231
protactinium
Pa
91
141
praseodymium
Pr
59
58
Ce
57
–
–
dubnium
Db
105
181
tantalum
Ta
73
93
niobium
Nb
41
51
vanadium
V
23
Cr
24
238
uranium
U
92
144
neodymium
Nd
60
–
seaborgium
Sg
106
184
tungsten
W
74
96
molybdenum
Mo
42
52
chromium
relative atomic mass
rutherfordium
Rf
hafnium
Hf
72
91
zirconium
Zr
40
48
titanium
La
lanthanoids
yttrium
Y
39
45
scandium
Ti
12
11
Sc
9
7
atomic symbol
Be
beryllium
Li
lithium
atomic number
4
3
Key
2
1
–
neptunium
Np
93
–
promethium
Pm
61
–
bohrium
Bh
107
186
rhenium
Re
75
–
technetium
Tc
43
55
manganese
Mn
25
–
plutonium
Pu
94
150
samarium
Sm
62
–
hassium
Hs
108
190
osmium
Os
76
101
ruthenium
Ru
44
56
iron
Fe
26
27
28
29
30
–
americium
Am
95
152
europium
Eu
63
–
meitnerium
Mt
109
192
–
curium
Cm
96
157
gadolinium
Gd
64
–
darmstadtium
Ds
110
195
platinum
Pt
Ir
iridium
78
106
palladium
Pd
46
59
nickel
Ni
77
103
rhodium
Rh
45
59
cobalt
Co
–
berkelium
Bk
97
159
terbium
Tb
65
–
roentgenium
Rg
111
197
gold
Au
79
108
silver
Ag
47
64
copper
Cu
–
californium
Cf
98
163
dysprosium
Dy
66
–
copernicium
Cn
112
201
mercury
Hg
80
112
cadmium
Cd
48
65
zinc
Zn
B
C
–
einsteinium
Es
99
165
holmium
Ho
67
–
nihonium
Nh
113
204
thallium
Tl
81
115
–
fermium
Fm
100
167
erbium
Er
68
–
flerovium
Fl
114
207
lead
Pb
82
119
tin
Sn
In
indium
50
73
germanium
Ge
32
28
silicon
Si
14
12
carbon
49
70
gallium
Ga
31
27
aluminium
Al
13
11
boron
6
–
mendelevium
Md
101
169
thulium
Tm
69
–
moscovium
Mc
115
209
bismuth
Bi
83
122
antimony
Sb
51
75
arsenic
As
33
31
phosphorus
P
15
14
nitrogen
N
7
–
nobelium
No
102
173
ytterbium
Yb
70
–
livermorium
Lv
116
–
polonium
Po
84
128
tellurium
Te
52
79
selenium
Se
34
32
sulfur
S
16
16
oxygen
O
8
–
lawrencium
Lr
103
175
lutetium
Lu
71
–
tennessine
Ts
117
–
astatine
At
85
127
iodine
I
53
80
bromine
Br
35
35.5
chlorine
Cl
17
19
fluorine
F
9
–
oganesson
Og
118
–
radon
Rn
86
131
xenon
Xe
54
84
krypton
Kr
36
40
argon
Ar
18
20
neon
Ne
10
4
5
helium
8
1
7
hydrogen
6
2
5
He
4
H
3
1
Group
The Periodic Table of Elements
16
Cambridge Lower Secondary Checkpoint

SCIENCE
0893/01
Paper 1
April 2023
45 minutes
You must answer on the question paper.
No additional materials are needed.
INSTRUCTIONS
• Answer all questions.
• Use a black or dark blue pen. You may use an HB pencil for any diagrams or graphs.
• Write your name, centre number and candidate number in the boxes at the top of the page.
• Write your answer to each question in the space provided.
• Do not use an erasable pen or correction fluid.
• Do not write on any bar codes.
• You should show all your working in the booklet.
• You may use a calculator.
INFORMATION
• The total mark for this paper is 50.
• The number of marks for each question or part question is shown in brackets [ ].
This document has 20 pages. Any blank pages are indicated.
IB23 05_0893_01/6RP
© UCLES 2023
[Turn over
36/72
2
1
This question is about the human excretory (renal) system.
(a) Complete these sentences about the structure and function of the excretory (renal) system.
The excretory (renal) system filters blood.
Blood enters the
where it is filtered, and urine is formed.
This urine passes along a tube called the
towards the bladder.
The urine is stored in the bladder.
Urine is released from the body through a different tube called the
.
[3]
(b) The table shows the percentage concentration of four substances in blood plasma and in urine.
substance
percentage concentration of substance
in blood plasma
in urine
ammonia
0.00
0.05
protein
9.00
0.00
salt
0.60
0.90
urea
0.03
2.00
Which substance has the greatest increase in the urine compared to blood plasma?
Choose from the list.
ammonia
protein
salt
urea
[1]
© UCLES 2023
0893/01/A/M/23
37/72
3
2
Aiko calculates the density of some objects.
(a) A block of iron has a mass of 19.68 g.
The volume of the block is 2.50 cm3.
(i) Write down the equation Aiko uses to calculate density.
density =
[1]
(ii) Calculate the density of Aiko's block of iron.
g / cm3
density =
[1]
(b) Aiko calculates the density of four objects.
Look at her results.
object
density
in g / cm3
A
2.7
B
8.4
C
0.002
D
13.6
Which object is a gas?
Circle the correct answer.
A
B
C
D
Explain your answer.
[1]
© UCLES 2023
0893/01/A/M/23
38/72
[Turn over
4
3
Look at the diagram of a vacuum flask.
Gabriella puts a hot liquid into the vacuum flask.
The flask keeps the hot liquid warm.
lid
stopper
hot liquid
plastic case
vacuum (no particles)
shiny silver surfaces
(a) Which material is most suitable to make the stopper?
Circle the correct answer.
copper
gold
iron
plastic
[1]
(b) (i) Suggest how the shiny silver surfaces help to keep the liquid warm.
[1]
(ii) The vacuum does not contain any particles.
Explain why the vacuum reduces the transfer of thermal energy.
[2]
© UCLES 2023
0893/01/A/M/23
39/72
5
(c) Gabriella removes the lid and the stopper from the vacuum flask.
Some of the hot liquid evaporates.
What happens to the temperature of the liquid that remains in the vacuum flask?
Explain why.
Use ideas about particles.
[3]
© UCLES 2023
0893/01/A/M/23
40/72
[Turn over
6
4
The Earth's crust is made of a number of large pieces.
(a) What is the name given to these pieces of the Earth’s crust?
Circle the correct answer.
earthquake
inner core
mantle
tectonic plates
[1]
(b) Look at the map showing the positions of earthquakes around the world in 2021.
earthquake
Suggest how the position of earthquakes provides evidence for the large pieces of the crust.
[1]
© UCLES 2023
0893/01/A/M/23
41/72
7
(c) Look at the two maps showing the jigsaw appearance of the continental coasts.
equator
equator
3000 million years ago
today
(i) What is meant by the jigsaw appearance of the continental coasts?
[1]
(ii) The continents have moved since 3000 million years ago.
Explain how the continents move.
[2]
© UCLES 2023
0893/01/A/M/23
42/72
[Turn over
8
5
The diagram shows a model of a hydrogen molecule.
= electron
H
H
(a) Name the type of bonding in a hydrogen molecule.
Explain how you can tell from the diagram.
[2]
(b) Look at the diagrams showing a chlorine atom and a chloride ion.
–
Cl
Cl
chlorine atom, Cl
chloride ion, Cl –
Describe how a chloride ion is made from a chlorine atom.
[1]
(c) Sodium chloride, NaCl, is made up of sodium ions, Na+, and chloride ions, Cl −.
Explain how the ions in sodium chloride are held together.
[1]
© UCLES 2023
0893/01/A/M/23
43/72
9
6
This is a question about photosynthesis and plant minerals.
(a) Look at the diagrams of different plant cells.
contains green pigment
A onion epidermal cells
B palisade cells
contains green pigment
C cells found in xylem
D guard cells
root hair
E epidermal cell in the root
Which two diagrams show plant cells that photosynthesise?
Choose from A, B, C, D and E.
and
© UCLES 2023
[2]
0893/01/A/M/23
44/72
[Turn over
10
(b) Carlos investigates the effect of magnesium on plant growth.
Carlos makes a hypothesis about the effect of magnesium on plant growth.
He uses the equipment in the diagram.
seedling
cotton wool
air tube
lid
beaker
solution
containing
minerals
In his first experiment Carlos:
• fills a beaker with a solution containing all the minerals needed for healthy growth
• assembles the equipment and seedling as shown in the diagram
• records the appearance of the seedling after four weeks.
Carlos repeats the experiment.
In his second experiment, he uses a solution that contains all the minerals needed for healthy
growth except magnesium.
(i) Carlos makes a hypothesis about the effect of magnesium on plant growth.
Suggest a suitable hypothesis.
[1]
© UCLES 2023
0893/01/A/M/23
45/72
11
(ii) In his first experiment, Carlos uses a solution with all the minerals needed for healthy
growth.
Explain why this is important.
[1]
(c) Carlos draws a diagram to show the appearance of the plant from the first experiment after
four weeks.
healthy green
leaves
seedling in first experiment
after four weeks
Carlos repeats his experiment again.
In his third experiment, he uses a solution that contains all the minerals needed for healthy
growth except nitrates.
Predict the appearance of the seedling left in the solution without nitrates after four weeks.
Give a reason for your answer.
[2]
(d) Which substance is made inside chloroplasts?
[1]
© UCLES 2023
0893/01/A/M/23
46/72
[Turn over
12
7
Ahmed hears two sounds, A and B.
Look at the waveforms for these two sounds.
waveform A
0
2
4
waveform B
6
8
time in
seconds
Give one similarity and one difference between waveform A and waveform B.
similarity
difference
[2]
© UCLES 2023
0893/01/A/M/23
47/72
13
8
When asteroids collide with the Earth, they make craters.
Chen uses a model to investigate the effect of asteroid collisions with the Earth.
In his investigation Chen:
• drops a rock into a container of soil
• measures the size of the hole in the soil made by the rock.
(a) Complete the sentences about Chen’s model.
In the model the rock represents
.
In the model the soil represents
.
In the model the hole represents
.
[2]
(b) Write down one strength and one limitation of his model of asteroid collisions with the Earth.
strength
limitation
[2]
© UCLES 2023
0893/01/A/M/23
48/72
[Turn over
14
9
Myxomatosis is a disease that kills rabbits.
(a) Describe the effect of myxomatosis on the size of a rabbit population.
[1]
(b) Foxes hunt rabbits for food.
The graph shows the population of foxes and the population of rabbits.
population
A
B
time
Tick (✓) the box that shows the population of rabbits.
line A
line B
Give two reasons for your answer.
1
2
[2]
© UCLES 2023
0893/01/A/M/23
49/72
15
10 Blessy makes some magnesium sulfate.
She adds an excess of magnesium to some dilute sulfuric acid until the reaction stops.
Unreacted magnesium is left at the bottom of the solution.
magnesium sulfate solution
unreacted magnesium
(a) Describe how Blessy separates the magnesium sulfate solution from the unreacted magnesium.
[1]
(b) Blessy wants to make solid magnesium sulfate from the magnesium sulfate solution.
Describe how she makes solid magnesium sulfate.
[1]
(c) Blessy now wants to make zinc chloride.
Write down the name of the metal and acid she uses to make zinc chloride.
metal
acid
[1]
© UCLES 2023
0893/01/A/M/23
50/72
[Turn over
16
11 The circuit diagram shows the circuit Priya makes using switches and identical lamps.
R
M
J
K
S
T
L
(a) Priya connects a meter to measure the current at position M in the circuit.
Draw the correct symbol for the meter she uses to measure the current.
[1]
(b) Priya opens and closes different switches.
Complete the table by writing if the:
• switches are open or closed
• lamps are on or off.
switch R
switch S
switch T
lamp J
closed
open
open
off
open
closed
closed
........................
........................ ........................ ........................
on
lamp K
lamp L
........................ ........................
off
off
........................
on
[3]
(c) Describe how Priya connects a voltmeter to measure the voltage across lamp J.
[1]
© UCLES 2023
0893/01/A/M/23
51/72
17
12 Pierre investigates the reaction between calcium carbonate and dilute hydrochloric acid.
The reaction gives off carbon dioxide gas.
Look at the equipment he uses.
glass wool plug
100 cm3 dilute hydrochloric acid
20 g calcium carbonate
102.34 g
X
(a) Write down the name of equipment X.
[1]
© UCLES 2023
0893/01/A/M/23
52/72
[Turn over
18
(b) Pierre measures the loss in mass every minute for 4 minutes.
Here are his results.
At the start the loss in mass is 0.0 g
1.5 g is the loss in mass after 4 minutes
3 minutes = a loss in mass of 1.2 g
After 1 minute the loss in mass is 0.8 g
1.1 g = 2 minutes
Complete his results table.
...............................................
loss in mass
in g
...............................................
...............
...............
...............
...............
...............
...............
...............
...............
...............
...............
[2]
© UCLES 2023
0893/01/A/M/23
53/72
19
BLANK PAGE
Permission to reproduce items where third-party owned material protected by copyright is included has been sought and cleared where possible. Every
reasonable effort has been made by the publisher (UCLES) to trace copyright holders, but if any items requiring clearance have unwittingly been included, the
publisher will be pleased to make amends at the earliest possible opportunity.
To avoid the issue of disclosure of answer-related information to candidates, all copyright acknowledgements are reproduced online in the Cambridge
Assessment International Education Copyright Acknowledgements Booklet. This is produced for each series of examinations and is freely available to download
at www.cambridgeinternational.org after the live examination series.
Cambridge Assessment International Education is part of Cambridge Assessment. Cambridge Assessment is the brand name of the University of Cambridge
Local Examinations Syndicate (UCLES), which is a department of the University of Cambridge.
© UCLES 2023
0893/01/A/M/23
54/72
[Turn over
© UCLES 2023
21
22
0893/01/A/M/23
55/72
40
38
Sr
strontium
88
56
Ba
barium
137
88
39
37
Rb
rubidium
85
55
Cs
caesium
133
87
actinoids
lanthanoids
–
calcium
potassium
–
actinoids
Ca
K
Ra
20
19
radium
89–103
24
23
Fr
104
57–71
magnesium
sodium
francium
178
89
Mg
Na
cerium
140
90
Th
thorium
232
lanthanum
139
89
Ac
actinium
–
231
protactinium
Pa
91
141
praseodymium
Pr
59
58
Ce
57
–
–
dubnium
Db
105
181
tantalum
Ta
73
93
niobium
Nb
41
51
vanadium
V
23
Cr
24
238
uranium
U
92
144
neodymium
Nd
60
–
seaborgium
Sg
106
184
tungsten
W
74
96
molybdenum
Mo
42
52
chromium
relative atomic mass
rutherfordium
Rf
hafnium
Hf
72
91
zirconium
Zr
40
48
titanium
La
lanthanoids
yttrium
Y
39
45
scandium
Ti
12
11
Sc
9
7
name
atomic symbol
Be
beryllium
Li
lithium
atomic number
4
3
Key
2
1
–
neptunium
Np
93
–
promethium
Pm
61
–
bohrium
Bh
107
186
rhenium
Re
75
–
technetium
Tc
43
55
manganese
Mn
25
–
plutonium
Pu
94
150
samarium
Sm
62
–
hassium
Hs
108
190
osmium
Os
76
101
ruthenium
Ru
44
56
iron
Fe
26
27
28
29
30
–
americium
Am
95
152
europium
Eu
63
–
meitnerium
Mt
109
192
–
curium
Cm
96
157
gadolinium
Gd
64
–
darmstadtium
Ds
110
195
platinum
Pt
Ir
iridium
78
106
palladium
Pd
46
59
nickel
Ni
77
103
rhodium
Rh
45
59
cobalt
Co
–
berkelium
Bk
97
159
terbium
Tb
65
–
roentgenium
Rg
111
197
gold
Au
79
108
silver
Ag
47
64
copper
Cu
–
californium
Cf
98
163
dysprosium
Dy
66
–
copernicium
Cn
112
201
mercury
Hg
80
112
cadmium
Cd
48
65
zinc
Zn
B
C
–
einsteinium
Es
99
165
holmium
Ho
67
–
nihonium
Nh
113
204
thallium
Tl
81
115
–
fermium
Fm
100
167
erbium
Er
68
–
flerovium
Fl
114
207
lead
Pb
82
119
tin
Sn
In
indium
50
73
germanium
Ge
32
28
silicon
Si
14
12
carbon
49
70
gallium
Ga
31
27
aluminium
Al
13
11
boron
6
–
mendelevium
Md
101
169
thulium
Tm
69
–
moscovium
Mc
115
209
bismuth
Bi
83
122
antimony
Sb
51
75
arsenic
As
33
31
phosphorus
P
15
14
nitrogen
N
7
–
nobelium
No
102
173
ytterbium
Yb
70
–
livermorium
Lv
116
–
polonium
Po
84
128
tellurium
Te
52
79
selenium
Se
34
32
sulfur
S
16
16
oxygen
O
8
–
lawrencium
Lr
103
175
lutetium
Lu
71
–
tennessine
Ts
117
–
astatine
At
85
127
iodine
I
53
80
bromine
Br
35
35.5
chlorine
Cl
17
19
fluorine
F
9
–
oganesson
Og
118
–
radon
Rn
86
131
xenon
Xe
54
84
krypton
Kr
36
40
argon
Ar
18
20
neon
Ne
10
4
5
helium
8
1
7
hydrogen
6
2
5
He
4
H
3
1
Group
The Periodic Table of Elements
20
Cambridge Lower Secondary Checkpoint

SCIENCE
0893/02
Paper 2
April 2023
45 minutes
You must answer on the question paper.
No additional materials are needed.
INSTRUCTIONS
• Answer all questions.
• Use a black or dark blue pen. You may use an HB pencil for any diagrams or graphs.
• Write your name, centre number and candidate number in the boxes at the top of the page.
• Write your answer to each question in the space provided.
• Do not use an erasable pen or correction fluid.
• Do not write on any bar codes.
• You should show all your working in the booklet.
• You may use a calculator.
INFORMATION
• The total mark for this paper is 50.
• The number of marks for each question or part question is shown in brackets [ ].
This document has 20 pages. Any blank pages are indicated.
IB23 05_0893_02/5RP
© UCLES 2023
[Turn over
56/72
2
1
This question is about a small mammal called a shrew.
(a) Look at the picture of two shrews from the same species.
Each shrew has a different fur colour.
Fur colour is controlled by genes.
Write down the name of the chemical that makes up genes.
[1]
(b) Eagles feed on shrews.
Scientists sample the population of the shrews living on ground that is dark in colour.
The diagram shows the population of shrews over two years.
The population of shrews for year 3 is not shown.
An eagle feeds on the shrews during years 2 and 3.
eagle
ground that is dark in colour
year 1
© UCLES 2023
year 2
0893/02/A/M/23
57/72
year 3
time
3
(i) The total population size of the shrews is the same during all three years.
Predict the numbers of white shrews and grey shrews in year 3.
Write your prediction in the table.
fur colour
number in population in year 3
…………………………
…………………………
[1]
(ii) Describe how natural selection explains the changes in the numbers of white and grey
shrews.
[3]
(iii) The scientists had to trap and release the shrews to get their results.
Write down two safety precautions the scientists took when trapping and releasing the
shrews.
1
2
[2]
© UCLES 2023
0893/02/A/M/23
58/72
[Turn over
4
2
Look at the diagram showing part of the Periodic Table.
H
Li
He
Be
B
C
N
O
F
Ne
Na Mg
Al
Si
P
S
Cl
Ar
K
Ca
transition elements
(a) The electronic structure of lithium is 2.1.
Write down the electronic structure of chlorine.
[1]
(b) Write down the symbol for the atom which has 12 protons in its nucleus.
[1]
(c) Neon is in Group 8 of the Periodic Table.
Neon is an unreactive gas at room temperature.
Argon is also in Group 8.
Suggest one property of argon.
[1]
© UCLES 2023
0893/02/A/M/23
59/72
5
3
Water moves through a plant.
(a) The table shows information about the pathway of water into and out of a plant.
Number 1 is the part where water enters the plant.
Number 5 is the part where water is lost from the plant.
Complete the table by writing the numbers 1, 2, 3, 4 and 5 to show the pathway of water into
and out of a plant.
One has been done for you.
part of plant
order of pathway
leaf
5
leaf xylem
....................
root hair cell
....................
root xylem
....................
stem xylem
....................
[1]
(b) Plants lose water from the surface of their leaves.
Write down the name of this process.
[1]
(c) A desert plant grows well due to its very waxy leaves.
High carbon dioxide levels reduce wax production in these plants.
Cars produce carbon dioxide.
Suggest what happens to the population of these desert plants growing near a new road.
[1]
© UCLES 2023
0893/02/A/M/23
60/72
[Turn over
6
4
This question is about waveforms.
(a) Look at the diagram of the waveform of a sound.
X
Y
Z
time
in seconds
W
Which letter shows the amplitude of the sound wave?
Circle the correct answer.
W
X
Y
[1]
Z
(b) The waveform for the sound shows several waves.
0
2
4
6
8
time
in seconds
How many complete waves are there in 8 seconds of the waveform?
number of waves
© UCLES 2023
0893/02/A/M/23
61/72
[1]
7
(c) The diagrams show how sound A interacts with sound B to make sound C.
waveform of sound A
0
2
4
6
8
time
in seconds
6
8
time
in seconds
6
8
time
in seconds
+
waveform of sound B
0
2
4
=
waveform of sound C
0
2
4
Describe how the waveform of sound A and waveform of sound B interact at:
time = 1 second
time = 3 seconds
[2]
© UCLES 2023
0893/02/A/M/23
62/72
[Turn over
8
5
Look at the diagram of the carbon cycle.
carbon dioxide in
the atmosphere
sunlight
combustion
process A
process B
decomposition
feeding
dead plants and animals
fossil fuels
(a) Write down the name of process A.
[1]
(b) Write down the name of process B.
[1]
(c) Write down one similarity between combustion and decomposition.
[1]
(d) Scientists believe that too much carbon dioxide in the atmosphere causes climate change.
Describe two possible effects of climate change.
1
2
[2]
© UCLES 2023
0893/02/A/M/23
63/72
9
6
Look at the data about some Group 1 elements.
element
melting point
in °C
atomic radius
in pm
lithium
181
145
sodium
98
180
potassium
64
220
rubidium
235
(a) Describe the trend in atomic radius as you go down Group 1.
[1]
(b) Predict the melting point of rubidium.
The melting point of rubidium is
°C.
[1]
(c) Sodium reacts with chlorine to make an ionic solid called sodium chloride.
Sodium chloride has a melting point of 808 °C.
Sodium chloride has a structure.
Name this type of structure.
[1]
7
Write down the names of these electrical symbols.
[2]
© UCLES 2023
0893/02/A/M/23
64/72
[Turn over
10
8
Here are some sentences about the collision theory for the formation of the Moon.
A
The less dense rocks eventually merged together to form the Moon.
B
This caused very high temperatures and the Earth’s outer layer melted.
C
A collision occurred between the Earth and a small planet.
D
The less dense rocks were ejected and cooled.
E
The dense iron from the cores of both planets merged to create the Earth.
F
The less dense rocks were captured by the Earth’s gravitational field.
(a) Put these sentences in the correct order to describe the collision theory.
Two have been done for you.
E
F
[3]
(b) In 1969, astronauts went to the Moon and collected rock samples.
Describe how these Moon rock samples provide evidence to support the collision theory.
[1]
(c) Suggest why the density of the Earth is greater than the density of the Moon.
Use ideas from the collision theory in your answer.
[1]
© UCLES 2023
0893/02/A/M/23
65/72
11
9
Scientists estimate one million species of plants and animals are at risk of extinction.
(a) Which factors cause a species to become extinct?
Tick (✓) the two correct factors.
changes in seasons
changes to the environment over time
increased reproduction
new diseases
new food sources
[2]
(b) Explain what is meant by the statement:
‘An animal is at risk of extinction.’
Use ideas about death rate and reproduction rate.
[1]
© UCLES 2023
0893/02/A/M/23
66/72
[Turn over
12
10 Look at the list of metals in order of reactivity.
The most reactive metal is at the top.
calcium
magnesium
zinc
increasing reactivity
iron
copper
silver
A piece of copper is dipped into silver nitrate solution.
Silver is made.
A blue solution of copper nitrate is also made.
(a) What is the name of this type of reaction?
Circle the correct answer.
crystallisation
decomposition
filtration
displacement
neutralisation
[1]
(b) Write the word equation for this reaction.
[1]
© UCLES 2023
0893/02/A/M/23
67/72
13
(c) Look at the list of metals and solutions.
Tick ( ✓) to show if the metal reacts with the solution.
copper + iron nitrate
magnesium + zinc nitrate
silver + magnesium nitrate
iron + zinc nitrate
Explain your answer.
[2]
© UCLES 2023
0893/02/A/M/23
68/72
[Turn over
14
11 Lily investigates which type of insulation is best at reducing the transfer of thermal energy from
hot water.
Look at the diagram of Lily’s experiment.
thermometer
hot water
insulation (cardboard, newspaper or bubble wrap)
glass beaker
bench
Look at her results.
time
bubble wrap
newspaper
cardboard
temperature
in seconds
time
temperature
time
temperature
in seconds
in seconds
0
83
0
85
0
85
60
67
60
81
60
81
120
75
120
79
120
79
180
71
180
76
180
77
240
68
240
72
240
75
300
65
300
68
300
73
(a) The unit of temperature is missing from the tables.
Write down the unit of temperature.
[1]
(b) Calculate the decrease in temperature in the 300 seconds for each beaker.
cardboard
newspaper
bubble wrap
[1]
© UCLES 2023
0893/02/A/M/23
69/72
15
(c) Before the investigation, Lily predicts,
‘Bubble wrap is the best insulator.’
Is her prediction correct?
Explain your answer.
[1]
(d) In one of Lily’s results tables, there is an anomalous result.
Circle the anomalous result in the table.
Give a reason for your answer.
[2]
(e) Lily improves her investigation.
Suggest two improvements Lily makes to her investigation.
1
2
[2]
© UCLES 2023
0893/02/A/M/23
70/72
[Turn over
16
12 Mike investigates the reaction between magnesium and dilute hydrochloric acid.
Look at part of the equipment he uses.
dilute hydrochloric acid
magnesium
(a) Write down the name of the equipment Mike uses to collect the gas and measure the
volume of the gas.
[1]
(b) Mike measures the volume of gas made every 30 seconds until the reaction stops.
Describe how Mike makes his results more reliable.
[1]
(c) Mike writes a risk assessment for his investigation.
Write down one safety risk and describe how Mike reduces this risk.
safety risk
how Mike reduces this risk
[2]
© UCLES 2023
0893/02/A/M/23
71/72
© UCLES 2023
21
22
0893/02/A/M/23
72/72
40
38
Sr
strontium
88
56
Ba
barium
137
88
39
37
Rb
rubidium
85
55
Cs
caesium
133
87
actinoids
lanthanoids
–
calcium
potassium
–
actinoids
Ca
K
Ra
20
19
radium
89–103
24
23
Fr
104
57–71
magnesium
sodium
francium
178
89
Mg
Na
cerium
140
90
Th
thorium
232
lanthanum
139
89
Ac
actinium
–
231
protactinium
Pa
91
141
praseodymium
Pr
59
58
Ce
57
–
–
dubnium
Db
105
181
tantalum
Ta
73
93
niobium
Nb
41
51
vanadium
V
23
Cr
24
238
uranium
U
92
144
neodymium
Nd
60
–
seaborgium
Sg
106
184
tungsten
W
74
96
molybdenum
Mo
42
52
chromium
relative atomic mass
rutherfordium
Rf
hafnium
Hf
72
91
zirconium
Zr
40
48
titanium
La
lanthanoids
yttrium
Y
39
45
scandium
Ti
12
11
Sc
9
7
name
atomic symbol
Be
beryllium
Li
lithium
atomic number
4
3
Key
2
1
–
neptunium
Np
93
–
promethium
Pm
61
–
bohrium
Bh
107
186
rhenium
Re
75
–
technetium
Tc
43
55
manganese
Mn
25
–
plutonium
Pu
94
150
samarium
Sm
62
–
hassium
Hs
108
190
osmium
Os
76
101
ruthenium
Ru
44
56
iron
Fe
26
27
28
29
30
–
americium
Am
95
152
europium
Eu
63
–
meitnerium
Mt
109
192
–
curium
Cm
96
157
gadolinium
Gd
64
–
darmstadtium
Ds
110
195
platinum
Pt
Ir
iridium
78
106
palladium
Pd
46
59
nickel
Ni
77
103
rhodium
Rh
45
59
cobalt
Co
–
berkelium
Bk
97
159
terbium
Tb
65
–
roentgenium
Rg
111
197
gold
Au
79
108
silver
Ag
47
64
copper
Cu
–
californium
Cf
98
163
dysprosium
Dy
66
–
copernicium
Cn
112
201
mercury
Hg
80
112
cadmium
Cd
48
65
zinc
Zn
B
C
–
einsteinium
Es
99
165
holmium
Ho
67
–
nihonium
Nh
113
204
thallium
Tl
81
115
–
fermium
Fm
100
167
erbium
Er
68
–
flerovium
Fl
114
207
lead
Pb
82
119
tin
Sn
In
indium
50
73
germanium
Ge
32
28
silicon
Si
14
12
carbon
49
70
gallium
Ga
31
27
aluminium
Al
13
11
boron
6
–
mendelevium
Md
101
169
thulium
Tm
69
–
moscovium
Mc
115
209
bismuth
Bi
83
122
antimony
Sb
51
75
arsenic
As
33
31
phosphorus
P
15
14
nitrogen
N
7
–
nobelium
No
102
173
ytterbium
Yb
70
–
livermorium
Lv
116
–
polonium
Po
84
128
tellurium
Te
52
79
selenium
Se
34
32
sulfur
S
16
16
oxygen
O
8
–
lawrencium
Lr
103
175
lutetium
Lu
71
–
tennessine
Ts
117
–
astatine
At
85
127
iodine
I
53
80
bromine
Br
35
35.5
chlorine
Cl
17
19
fluorine
F
9
–
oganesson
Og
118
–
radon
Rn
86
131
xenon
Xe
54
84
krypton
Kr
36
40
argon
Ar
18
20
neon
Ne
10
4
5
helium
8
1
7
hydrogen
6
2
5
He
4
H
3
1
Group
The Periodic Table of Elements
20