Notesale: Turn your study into money

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CHEMISTRY B

OCR 2024
GCSE Chemistry B (Twenty First Century Science)
J258/02 Depth in Chemistry (Foundation Tier)
With Marking Scheme Merged

Oxford Cambridge and RSA

Tuesday 11 June 2024 – Morning
GCSE (9–1) Chemistry B (Twenty First Century Science)
J258/02 Depth in Chemistry (Foundation Tier)
Time allowed: 1 hour 45 minutes
You must have:
• a ruler (cm/mm)
• the Data Sheet for GCSE (9-1) Chemistry B
(inside this document)
You can use:
• a scientific or graphical calculator
pencil

F

• an HB

*

J

2

5

8

0

2

*

Please write clearly in black ink
...

Centre number

Candidate number

First name(s)
Last name
INSTRUCTIONS
• Use black ink
...

• Write your answer to each question in the space provided
...
The question numbers must be clearly shown
...

• Where appropriate, your answer should be supported with working
...

INFORMATION
• The total mark for this paper is 90
...

• Quality of extended response will be assessed in questions marked with an asterisk (*)
...

ADVICE
• Read each question carefully before you start your answer
...


(a) The student uses small, coloured beads to represent the protons and neutrons in the nucleus of
the model
...

Complete the diagram to show the correct arrangement of electrons in the
atom
...


Key
Proton
Neutron

Nucleus contains
5 protons and
6 neutrons

[2]
(b) Complete the sentences
...


ions

negative

neutral

neutrons

Atoms contain a nucleus with a
...


positive

protons

charge
...

[2]

© OCR 2024

3
(c) The bead the student uses to represent a proton has a diameter of 1
cm
...


If they make their model to scale, what is the diameter of the model atom?
Put a ring around the correct option
...

The particles in each atom are shown in the table
...
1

B

8

8

2
...
8
...

Atom
...


...
The student is correct
...

Atom A has one electron in the outer shell
...

Atom A has two shells of electrons
...

The diagram shows the methods to prevent corrosion that are used on some parts of a bike
...
Some work by
sacrificial protection
...


Coating

Oil

How the coating
prevents corrosion

Forms a protective
barrier
...


[2]

© OCR 2024

5
(b) Iron to make bikes is extracted from iron oxide
...
When iron corrodes it reacts with oxygen to form iron oxide
...

Extraction: Fe2O3 + 3CO
Corrosion: 4Fe + 3O2

2Fe + 3CO2

2Fe2O3

Explain the difference between oxidation and reduction
...



...


...


...
[3]

© OCR 2024

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6
3

A scientist works in a laboratory that does research into medicines
...


(a) Which statements about formulations are true and which are false?
Tick (3) one box in each row
...

Formulations contain elements bonded together to make a
single compound
...

[2]
(b) The scientist uses distilled water for their medicines
...

What changes happen during simple distillation?
Tick (3) two boxes
...

Explain why tap water is not a pure substance
...


...

The diagram shows their results
...

Put a ring around the correct options
...

The chromatography paper acts as the stationary / mobile phase
...

[2]
(e) The scientist measures the melting point of some of the substances they use to make medicines
...

Substance

Melting point (°C)

A

102

B

151–156

C

2032

D

1040–1056

Which two substances are pure?
Explain your reasoning
...

Explanation
...

[2]

© OCR 2024

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8
4

The graph shows how the percentages of some gases in the atmosphere have changed from
4400 million years ago (MYA) until now
...

Explain your reasoning
...
MYA
...


...


...

All of the hydrogen left the atmosphere over 3000 MYA
...

The percentages of gases in the atmosphere have stayed
approximately constant for the last 500 million years
...

[2]

© OCR 2024

9
(c) Scientists think that the Earth’s early atmosphere came from volcanoes
...

Percentage composition
Volcano gas

Earth’s atmosphere
4400 MYA

Water vapour

92%

5%

Carbon dioxide

4
...
5%

4%

Gas

(i)

Scientists think that water vapour from volcanoes turned into liquid water over 4000 MYA
and formed the Earth’s oceans
...


...


...
[2]

(ii) Which of these statements support the idea that the Earth’s atmosphere came from volcanoes?
Use the data in the table and the graph
...

Hydrogen comes from volcanoes and was in the Earth’s atmosphere 4400 MYA
...

The Earth’s atmosphere 4400 MYA and volcano gases both contain carbon dioxide
...

[2]

© OCR 2024

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10
5
(a) Ammonium sulfate is made in an industrial process for use as a fertiliser
...


(i)

ammonium carbonate

+

calcium sulfate

(NH4)2CO3(aq)

+

CaSO4(s)

ammonium sulfate
(NH4)2SO4(aq)

+

a by-product

+

CaCO3(s)

Which method can be used to separate aqueous ammonium sulfate from the mixture left at the
end of the reaction
...

Distillation

Evaporation

Filtration

Titration

[1]
(ii) Explain the difference between what happens to by-products and waste products from
industrial processes
...


...


...

Hydrochloric acid
Nitric acid
Phosphoric acid
Sulfuric acid
[1]

© OCR 2024

11
(c) Chemicals are usually made in industry in continuous processes
...

(i)

State one advantage of using continuous processes in industry
...


...


...
[1]

© OCR 2024

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12
6
(a)* A student has samples of two solid compounds
...

They decide to do a flame test on each compound
...

Describe how the student should do their flame test and their test using dilute sodium hydroxide
...


...


...


...


...


...


...
[6]

© OCR 2024

13
(b) The student uses an emission spectroscopy machine to find out the metal ions in some other
compounds
...

They then test an unknown mixture
...


Lithium ions

Sodium ions

Unknown mixture

(i)

Which statements about the unknown mixture are true and which are
false? Tick (3) one box in each row
...

The information in the diagram is not enough to identify
all the ions in the unknown mixture
...

[2]
(ii) Which statement about using tests to identify ions is true?
Tick (3) one box
...

Emission spectroscopy is more sensitive than chemical tests
...

Reactions used in chemical tests are very slow
...

Fig
...
1 shows the structure of ethene
...
7
...

(a) Draw the structure of a section of poly(ethene) formed from three ethene monomers
...

Calculate the number of carbon and hydrogen atoms in this poly(ethene) molecule
...

Number of hydrogen atoms =
...
Calculate the relative formula mass of this poly(ethene) molecule
...


Relative formula mass =
...
Fig
...
2 shows a three-dimensional model of a chloroethene monomer
...
7
...

Write the molecular formula of chloroethene
...
[1]

(ii) Fig
...
3 shows the structure of the repeating unit of poly(ethene)
...
7
...


[2]
(d)
(i) Explain why ethene is considered to be an alkene and chloroethene is not an alkene
...


...


...
[1]
© OCR 2024

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16
BLANK PAGE

PLEASE DO NOT WRITE ON THIS PAGE

© OCR 2024

17
8* A student does some experiments to find out the order of reactivity of some metals
...

3
They stop timing after 5 minutes if 10 cm gas have not been made
...

The table shows their results
...

Explain your reasoning
...



...


...


...


...


...


...
[6]
© OCR 2024

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18
9
(a) Table 9
...

Table 9
...
1 to complete the
graph
...

160

140

120

100

Boiling
80
point (°C)

60

40

20

04

5

6
7
8
Number of carbon atoms in formula

9

10
[3]

(ii) Use your graph to predict the boiling point of heptane,
C7H16
...


Boiling point of heptane =
...
Table 9
...

Complete Table 9
...

Table 9
...

[1]

(c) Alkanes come from crude oil
...

Chemicals in crude oil have different boiling points
...

Crude oil is a feedstock for the petrochemical industry
...

[2]

© OCR 2024

21
BLANK PAGE

PLEASE DO NOT WRITE ON THIS PAGE

Turn over for the next question

© OCR 2024

Turn over

22
10 Millions of tonnes of carbon dioxide (CO2) are added to the air in the UK every year
...

(a) Schemes are being developed to remove carbon dioxide from power station waste gases
...

Explain why it is important to remove carbon dioxide, despite the cost
...


...


...


...
[3]

(b) The UK government says that the mass of carbon dioxide added to the air during the year 2020
decreased by 400 million tonnes compared to 1990
...

Calculate the mass of carbon dioxide added to the air during 1990
...
million tonnes [3]

© OCR 2024

23
(c) Scientists are developing a new scheme to remove carbon dioxide from the air and store it in
empty oil fields
...


Burning fossil fuels in the UK will add 230 million tonnes of carbon dioxide to the air each
year
...


There is enough space in UK oil fields to store all this carbon dioxide for at least the next
100 years
...

3
< 2
...
3 × 10 million tonnes
6
< 2
...
3 × 10 million tonnes

[1]
(ii) The demand for energy for electricity is one factor that affects the amount of fossil fuels we burn
...


...
[1]

© OCR 2024

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24
BLANK PAGE

PLEASE DO NOT WRITE ON THIS PAGE

© OCR 2024

25
11 A student investigates the rate of reaction when a solid reacts with a dilute acid
...

The student collects the gas in a measuring cylinder over water
...

Include labels on your diagram
...
Suggest another method they could use to get more accurate readings
...


...

The student draws a tangent to the curve at the point where time = 120 s
...


3
Gradient =
...

The increase in volume and time at 180 s
...

3
The time taken to make 90 cm gas
...

[1]

© OCR 2024

27
(c) The student repeats their experiment using different conditions
...

Draw lines to connect each change in condition with its correct explanation for the increase
in rate
...


Increased
temperature

Frequency of particle collision
increases because particles are
closer together
...

[2]

END OF QUESTION PAPER

© OCR 2024

28
EXTRA ANSWER SPACE
If you need extra space use this lined page
...


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...


...


...


...


...


...


...


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...


Foundation
GCSE
Chemisty B Twenty First Century Science
J258/02: Depth in Chemistry (Foundation Tier)
General Certificate of Secondary Education

Mark Scheme for June 2024

Oxford Cambridge and RSA Examinations

OCR (Oxford Cambridge and RSA) is a leading UK awarding body, providing a wide range of
qualifications to meet the needs of candidates of all ages and abilities
...


It is also responsible for developing new specifications to meet national requirements and
the needs of students and teachers
...

This mark scheme is published as an aid to teachers and students, to indicate the requirements
of the examination
...
It does not
indicate the details of the discussions which took place at an examiners’ meeting before
marking commenced
...

Mark schemes should be read in conjunction with the published question papers and the
report on the examination
...


Make sure that you have accessed and completed the relevant training packages for on -screen marking: RM Assessor Online Training; OCR
Essential Guide to Marking
...


Make sure that you have read and understood the mark scheme and the question paper for this unit
...


3
...


MARKING
1
...


2
...


3
...
It is essential that you meet the RM Assessor 50% and 100% (traditional 50% Batch 1 and 100%
Batch 2) deadlines
...


4
...


2

J258/02
5
...


where a candidate crosses out an answer and provides an alternative response, the crossed out response is not marked and gain s no
marks

b
...


6
...
If the
candidate has continued an answer there then add a tick to confirm that the work has been seen
...


There is a NR (No Response) option
...
g
...
g
...


Note: Award 0 marks – for an attempt that earns no credit (including copying out the question)
...


The RM Assessor comments box is used by your Team Leader to explain the marking of the practice responses
...
Do not use the comments box for any other reason
...


9
...
The report should contain notes on particular strengths displayed as well as common errors or weaknesses
...


3

J258/02
10
...
The
indicative scientific content in the Guidance column indicates the expected parameters for candidates’ answers, but be prepar ed to recognise
and credit unexpected approaches where they show relevance
...

Once the level is located, award the higher or lower mark:
The higher mark should be awarded where the level descriptor has been evidenced and all aspects of the communication statement (in
italics) have been met
...

In summary:
The skills and science content determines the level
...


Level of response questions on this paper are 6 and 8
...


Mark scheme

Annotations available in RM Assessor

Annotation

Meaning
Correct response
Incorrect response
Omission mark
Benefit of doubt given
Contradiction
Rounding error
Error in number of significant figures
Error carried forward
Level 1
Level 2
Level 3
Benefit of doubt not given
Noted but no credit given
Ignore

5

June 2024

J258/02
12
...

Annotation

Meaning

/

alternative and acceptable answers for the same marking point



Separates marking points

DO NOT ALLOW

Answers which are not worthy of credit

IGNORE

Statements which are irrelevant

ALLOW

Answers that can be accepted

()

Words which are not essential to gain credit

__

Underlined words must be present in answer to score a mark

ECF

Error carried forward

AW

Alternative wording

ORA

Or reverse argument

6

J258 02
13
...
This mate rial includes:
•

the specification, especially the assessment objectives

•

the question paper

•

the mark scheme
...

You should ensure also that you are familiar with the administrative procedures related to the marking process
...
If you are examining for the first time, please read carefully Appendix 5 Introduction to Script Marking:
Notes for New Examiners
...
Your first point of contact is your Team Leader
...


AO1
...


AO1
...

Apply knowledge and understanding of scientific ideas and scientific enquiry, techniques and procedures
...
1

Apply knowledge and understanding of scientific ideas
...
2

Apply knowledge and understanding of scientific enquiry, techniques and procedures
...
1

Analyse information and ideas to interpret and evaluate, make judgements and draw conclusions and develop and improve
experimental procedures
...


AO3
...


AO3
...


AO3
...


AO3
...


AO3
...


AO3
...


AO3
...


AO3
...


8

J258 02

1

Mark scheme

Question
(a)

Answer
2 electrons shown in first shell / 3 electrons in
second shell / total of 5 electrons
✓

✓

June 2024

AO
Marks element
2
2
...
1

1
2

2
...
1a

1

2
...


✓

IGNORE mention of electrons/shells

J258/02

Mark scheme

Question
2

Answer

Marks

(a)

2
Coating

June 2024

AO
element
1
...

All correct = 2 marks
Two coatings correct = 1 mark

Oil

Forms a protective
barrier
...


✓

Oxidation is gain of oxygen / loss of electrons

3

Reduction is loss of oxygen / gain of electrons

Iron is oxidised during corrosion AND iron/iron oxide
is reduced during extraction / carbon monoxide is
oxidised during extraction AND iron/iron oxide is
reduced

2 x 1
...
1

J258/02

Mark scheme

Question
3
(a)

Answer

Marks
2
True

Formulations are a mixture of
compounds
...
1
All correct = 2 marks
Two correct = 1 mark

✓

Formulations contain elements bonded
together to make a single compound
...


False

June 2024

✓

2

1
...
1

ALLOW other chemicals/ metal ions

2

2
...
1a

✓
✓

They have a sharp melting point/ single value of
melting point AW

ALLOW Melting Points do not vary

✓

11

J258/02

Mark scheme

Question
4

Answer
2000 (MYA)

(a)

AO
element

3

3
...
1a

✓

The percentages of gases in the atmosphere have
stayed constant for approximately 500 million years
...
1
3
...
1

2

3
...

(c)

(i)

below the boiling point of water / below 1000C
because the water (cooled and) condensed

✓

✓

(ii) Hydrogen comes from volcanoes and was in the
Earth’s atmosphere 4400 MYA
...


✓

12

IGNORE cold

J258/02

Question
5
(a)

Mark scheme

(i)
(ii)

Filtration

Answer

✓

A by-product has a use / is used to make a product/ is
useful / can be sold

✓

June 2024

AO
Marks element
Guidance
1
2
...
1
IGNORE may be reused/recycled

a waste product must be disposed of /goes to landfill
✓

(b)
(c)

Sulfuric acid

(i)

✓

Keeps going all the time / 24 hours / no need to stop
and start / makes more product in a day idea /
constant supply

(ii)

1
1

2
...
1

1

2
...


June 2024

AO
Marks element
6
2 x 1
...
1a
2 x 2
...

There is a well-developed line of reasoning which is
clear and logically structured
...

Level 2 (3–4 marks)
Makes statements to describe a procedure and its
results
...

There is a line of reasoning presented with some
structure
...

Level 1 (1–2 marks)
Makes a statement to describe a procedure or result for
at least one test
...
The information is in the most part relevant
...
2 and 3
...
2 Apply techniques / procedures
...

(b)

(i)

2

3
...
2

TTF
(ii) Emission spectroscopy is more sensitive than chemical
tests
...
1
ALLOW for 1 mark Hexane structure
DO NOT ALLOW any H with more than 1
bond

2

2
...
1

1

2
...
1

✓

✓

✓

(ii)

correct atoms shown C2H3Cl

✓
DO NOT ALLOW answers which are not
(C2H3Cl)n

no double bond between carbon atoms and
brackets, continuation lines and n ✓
(d)

IGNORE brackets
ALLOW different order e
...
Cl C2H3

(i)

✓
ethene is a hydrocarbon with a double bond
✓
chloroethene contains chlorine / is not a hydrocarbon

2

2
...
1

✓

15

ALLOW If no other marks are awarded, 1
mark for ‘ethene contains a double bond’
...

Level 3 (5–6 marks)
Gives correct order for all five metals, explains how the
data is used and explains why all metals are not tested
...
The information presented
is relevant and substantiated
...

OR
Gives correct order for all five metals and explains why
all metals are not tested
...
The information presented is relevant and
supported by some evidence
...

OR
Explains why all metals are not tested
There is an attempt at a logical structure with a line of
reasoning
...

0 marks
No response or no response worthy of credit
...
2b AO3
...
2 of reactivity
• (uses information from reaction with water
and) states order sodium, calcium,
magnesium
• (uses information from all reactions to give
complete order) sodium calcium
magnesium zinc iron
...
2: Explains how data is used
...
2 Why all metals are not tested
• idea that there is no need to test sodium
and calcium because order already
known
• sodium and calcium may react too
vigorously with acid / safety hazard

J258/02

9

Mark scheme

Question
(a)

Answer

(i)

all plots plotted correctly

best fit line

Marks
3

✓✓

June 2024

AO
element
1
...
2

1
2

2
...
1

✓

(b)
(c)

C2H5

✓

Crude oil is a feedstock for the petrochemical
industry
...


✓

17

J258/02

Mark scheme

Question
10
(a)

AO
Marks element
Guidance
3
2 x 2
...
2a

IGNORE indirect effects e
...
habitat loss/damage
to ecosystems
ALLOW examples of extreme weather e
...

tornadoes/droughts/wildfires

benefits outweigh the risk/cost / idea of long term
benefits but short term costs

(b)

✓

FIRST CHECK THE ANSWER ON ANSWER LINE
If answer = 816 (millions of tonnes) award 3
marks
Substitution: 49 = (400÷mass added) x 100

3

2
...
g
...
g
...
32653…
...
g
...
3 x 104 millions tonnes ✓

1

3
...
g
...
✓

1

1
...
2

✓
3
...
47 (cm3/s) award 3 marks

(ii)

IGNORE small gaps only

1

Shows (132-48) OR (21 x 4) OR 84 in working

84/180 = 0
...
3b
ALLOW 2 or more sig figs from 0
...
2

✓

ALLOW MP3 ECF on incorrect readings but
substitution must be correct
For MP3 answer must be given to 2 or more
significant figures seen anywhere
...
46 if 84 and 180 are shown in
working

The rate of reaction at 120s

1

19

3
...
2

All correct = 2 marks
1 or 2 correct = 1 mark
IGNORE any box if two lines are shown



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