Notesale: Turn your study into money

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CHEMISTRY A

OCR 2024
GCSE Chemistry A (Gateway Science)
J248/01 (Foundation Tier)
With Marking Scheme Merged

Oxford Cambridge and RSA

Friday 17 May 2024 – Morning
GCSE (9–1) Chemistry A (Gateway Science)
J248/01 (Foundation Tier)
Time allowed: 1 hour 45 minutes
You must have:
• a ruler (cm/mm)
• the Data Sheet for GCSE (9–1) Chemistry A
(inside this document)

F

You can use:
• a scientific or graphical calculator
• an HB pencil

*

J

2

4

8

0

1

*

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
...

Write your answer to each question in the box provided
...

How are the ions held together in sodium chloride?
A Covalent bonds
B Delocalised electrons C
Electrostatic forces D
Intermolecular forces

Your answer
5

[1]

Which equipment is used for filtration?
A

B

C

D

Your answer

© OCR 2024

[1]

Turn over

4
6

Which scientist suggested the idea that electrons exist in electron shells?
A Bohr
B Dalton
C Rutherford D
Thomson
Your answer

7

[1]

Which row describes a formulation?
Description

Amount of chemicals

A

compound

exact

B

mixture

exact

C

compound

random

D

mixture

random

Your answer
8

[1]

The table shows information about some atoms and ions
...
0 g of aluminium reacts with 43
...
4 g of aluminium
chloride
...
6 g of aluminium
chloride? A 22
...
0 g C
86
...
6 g
Your answer

[1]

12 The table shows the start and end temperatures of four reactions
...
0

19
...
0

15
...
0

23
...
0

21
...

Which row describes what happens to the inert electrodes during the electrolysis of molten
copper chloride?
A Mass of both electrodes decreases B
Mass of both electrodes increases
C Mass of one electrode increases, mass of one electrode decreases
D Mass of one electrode increases, mass of one electrode stays the same

Your answer

[1]

15 The diagram shows the electrolysis of molten sodium chloride
...

(a) Draw lines to connect each temperature with the particle model of water
...

1

H
1

(i)

8

O
16

How many protons does an oxygen atom have?

...
[1]

(iii) What is the relative charge of a proton?

...


O
H

O

H
H

Model 1

H

Model 2

Model 3

Which model would you use to show the volume of a water molecule?
Explain your answer
...

Reason
...

[2]
(d) Water is formed from the reaction of hydrogen, H2, and oxygen, O2
...

Explain how you can tell from the equation
...


...

(a) Complete the sentences about how the student investigates the neutralisation
reaction
...

Clamp stand

Conical flask

Measuring cylinder

pH meter

Pipette

Thermometer

The student uses a
...

They use a
...

[2]

(b) The student adds universal indicator to the acid
...

Colour of indicator before alkali is added

Red

Colour of indicator when solution is neutral

Green

Colour of indicator when too much alkali has been added

Yellow

Do you agree with the student?
Tick (3) one box
...

The student is partly correct
...

Explain your answer
...


...

[3]

© OCR 2024

13
(c) The table shows the volume of alkali the student adds in each experiment
...
2

2

24
...
9

4

24
...

Give your answer to 3 significant figures
...
cm [3]
(d) Complete the word equation for a neutralisation reaction
...

[2]

(e) Which two ions react together in neutralisation reactions to form H2O?
Put a ring around two ions
...

Key:
Recycled
Not able to be recycled
Not put into recycling
0

10

20

30

40

50

60

70

80

90 100

Amount of plastic waste (%)
The town generates a total of 45 000 kg of plastic waste in a year
...


Mass of plastic waste not able to be recycled =
...
Polymers have covalent bonds between the atoms
...


...
[1]

(ii) Describe two differences between a polymer used to make a plastic bag and a polymer used
to make a plastic bottle
...


...


...

The scientist says that a polymer that stretches will not be suitable for making a
ruler
...


Before stretching

After stretching

Explain why the scientist is correct
...


...

[2]
(d) The properties of four different polymer samples are shown in the table
...
0

PVC

110

12
...
1

PE

125

10
...


...
[1]

(ii) The molecular formula of the monomer used to make PET is C10H10O5
...


...

Sodium sulfate, water and carbon dioxide are made
...


Na2CO3(s) + H2SO4(aq)


...

What does (aq) mean?

...
The student wants to collect the gas formed
...


Conical flask

Sulfuric acid

Sodium carbonate

[2]

© OCR 2024

17
(b) The table shows the student’s results
...
0

2

2
...
5

6

4
...
9

10

5
...
1

14

5
...

Six points have already been plotted
...
0
5
...
0
Volume
of gas 3
...
0
1
...
0 0

1

2

3

4

5

6

7
8
9
Time (minutes)

10

11

12

13

14

(ii) Draw a curve of best fit
...
5 minutes
...
cm [1]

© OCR 2024

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18
3
(iv) The student collects 5
...


The student wants to collect more gas
...

Use a larger conical flask
Use less sodium carbonate
Use less sulfuric acid
Use more sulfuric acid
[1]

© OCR 2024

19
BLANK PAGE

PLEASE DO NOT WRITE ON THIS PAGE

© OCR 2024

Turn over

20
20
(a)* A Periodic Table is shown with two sections, A and B
...

State and explain if element X is found in section A or B
...


...


...


...


...


...


...
[6]

© OCR 2024

21
(b) In his Periodic Table, Mendeleev noticed that when elements were arranged in order of
atomic mass, some elements seemed to be in the wrong place
...
Use words from the list
...

He predicted that some elements
...
these elements
...


Li

He

Explain why Group 1 elements are reactive, but Group 0 elements are unreactive
...


...


...
7 × 10
A diamond is 4
...


m wide
...

Two

Four

Seven

[1]

(b) Calculate the number of carbon atoms that fit in the width of the
diamond
...


Number of carbon atoms =
...


Explain why diamond cannot conduct electricity
...


...


...


(i)

Form of carbon

Conducts
electricity?

Conducts heat?

Melting point

X

yes

yes

very high

Y

no

yes

high

Z

no

no

very high

Which form of carbon should you choose to use as an electrode in an electrolysis experiment
with a molten electrolyte?
Explain your answer
...

Reason
...

[2]

(ii) All of the melting points in the table are high
...

Electrodes need to remain liquid, and not freeze at low temperatures
Electrodes need to remain liquid, and not melt at high temperatures
Electrodes need to remain solid, and not freeze at low temperatures
Electrodes need to remain solid, and not melt at high temperatures
[1]

© OCR 2024

Turn over

24
22
(a) A scientist investigates dissolving four different tablets in
water
...

3
They add each tablet to 20 cm of water and time how long it takes for the tablet to

dissolve
...

Surface area
of tablet
2
(cm )

Volume
of tablet
3
(cm )

Surface area
to volume

Time taken to
dissolve

ratio

(seconds)

A

2
...
3

9
...
5

0
...
5 : 1

27

C

1
...
2

D

3
...
2

Tablet

(i)

62
15
...


Surface area to volume ratio =
...

As the surface area to volume ratio
...
time to dissolve
...
Explain why the scientist is incorrect
...


...

[2]

© OCR 2024

25
(b) The scientist performs thin layer chromatography on solutions of each of the tablets
...

State what the scientist could use to see the spots
...
[1]

(ii) After the scientist uses a method to see the spots, the chromatogram for Tablet A is shown
...


Rf value =
...

Different separation methods are used depending on the mixture
...

Separation method

Crystallisation

Mixture
Insoluble solid
and liquid

Filtration

Solution containing a
soluble solid dissolved
in a liquid

Fractional
distillation

Three liquids with
different boiling points
[2]

(b) The student decides to use simple distillation to separate a mixture
...


Flask containing mixture
Collection flask
Bunsen burner

(i)

A liquid in the mixture is flammable
...


...
[1]

© OCR 2024

27
(ii) The student wants to record the boiling point of the pure liquid that is collected in the collection
flask
...


...
[1]

(c) The pure liquid collected has the molecular formula (C2H5)2O and a boiling point of 35
°C
...

The empirical formula is CH2
...

The pure liquid contains two compounds
...

The pure liquid will be a gas at above 35 °C
...

Relative atomic mass (Ar): C = 12
...
0 O = 16
...
[3]

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
Chemistry A (Gateway Science)
J248/01: Paper 1 (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

J248/01
5
...
Where no
alternative response has been provided, examiners may give candidates the benefit of the doubt and mark the crossed out response where
legible
...
Enter a mark for each question answered into RM
assessor, which will select the highest mark from those awarded
...
)
Multiple Choice Question Responses
When a multiple choice question has only a single, correct response and a candidate provides two responses (even if one of these responses
is correct), then no mark should be awarded (as it is not possible to determine which was the first response selected by the candidate)
...

Contradictory Responses
When a candidate provides contradictory responses, then no mark should be awarded, even if one of the answers is correct
...

The response space should be marked from left to right on each line and then line by line until the required number of responses have been
considered
...
Examiners will have to apply judgement as to whether a ‘second response’
on a line is a development of the ‘first response’, rather than a separate, discrete response
...
)

3

J248/01

Mark Scheme

June 2024

Short Answer Questions (requiring a more developed response, worth two or more marks)
If the candidates are required to provide a description of, say, three items or factors and four items or factors are provided, then mark on a
similar basis – that is downwards (as it is unlikely in this situation that a candidate will provide more than one response in each section of the
response space
...
Examiners will need to apply professional judgement as to
whether the second (or a subsequent) response is a ‘new start’ or simply a poorly expressed continuation of the first response
...


Always check the pages (and additional objects if present) at the end of the response in case any answers have been continued there
...


7
...

Team Leaders must confirm the correct use of the NR button with their markers before live marking commences and should check this
when reviewing scripts
...


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
...


4

J248/01
10
...
The
indicative scientific content in the Guidance column indicates the expected parameters for candidates’ answers, but be prepared 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 question on this paper is 20(a)
...


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

6

June 2024

J248/01

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

7

June 2024

J248/01
13
...
This material 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
...


9

J248/01

Mark Scheme

June 2024

For answers to Section A if an answer box is blank ALLOW correct indication of answer e
...
circled or underlined
...
1

1

2
...
1

1

1
...
2

1

1
...
1

1

2
...
2

1

2
...
1

12

B✓

1

2
...
2

14

D

1

1
...
2

15

B

✓

✓
✓
✓

Guidance

J248/01

Mark Scheme

Question

Answer

Marks

16 (a)

2
0 °C

June 2024
AO
Guidance
element
2 x 1
...
1

1

2
...
1

2

2 x 3
...
1
ALLOW H has bonded with oxygen / it has joined
with oxygen / oxygen has been gained
IGNORE water is formed / loss of electrons /
molecule
DO NOT ALLOW mixed with oxygen

12

J248/01

Mark Scheme

Question
17 (a)

pH meter
(b)

Marks

AO
element



2

2 x 1
...
2a

Answer
Measuring cylinder / pipette

June 2024



The student is partly correct

Universal indicator turns red in acid AND green in neutral

ALLOW red when no alkali added AND green

solutions

when neutral





Universal indicator is blue in alkali / not yellow in alkali
(c)

3 sig figs:
= 24
...
125 scores 2 marks

✓
ALLOW ECF from incorrect total volume

✓

ALLOW ECF if significant figures are correct from
incorrect calculation of mean volume

✓

Water

3 x 1
...
5 scores 1 mark

✓

24
...
4 + 23
...
0 ÷ 4 / 96
...
125

(e)



First check the answer on the answer line
If answer = 24
...
2 + 24
...
9 + 24
...
5

(d)

Guidance

2 x 1
...
1

J248/01

Mark Scheme

Question
18 (a)

Answer

Marks

First check the answer on the answer line
If answer = 9000 (kg) award 3 marks
Correctly takes 50 and 30 from chart
(50-30) = 20 (%)

3

June 2024
AO
element
3 x 2
...
1

2

2 x 2
...
1b

✓
IGNORE rulers should not be stretchy

(stretch makes) scale/lines/graduations stretch apart
✓

✓
ALLOW inaccurate / different / reading is too small
ALLOW measurements would stretch

measurements are incorrect / too small

(d)

(i)

The lower the melting point, the further the sample can
stretch (before breaking) / ORA

(ii)

C2H2O

1

✓

✓

1

3
...
2

ALLOW the lower the melting point the higher the
distance (stretched before breaking)
ALLOW C2H2O1
ALLOW any order of symbols
DO NOT ALLOW C2H2O / C2H2O

15

J248/01

Mark Scheme

Question
19 (a)

Answer

Marks

AO
element

1

2
...
1

ALLOW solution
IGNORE soluble in water

✓

(i)

Na2SO4

(ii)

aqueous / dissolved in water

June 2024

✓

Guidance

DO NOT ALLOW liquid
(iii) Method for gas collection (such as gas syringe,
displacement of water in upturned tube)

✓

2

2 x 3
...
2

± ½ small square

1

2
...
8 cm3

✓

1

16

2
...
1 cm3
ECF

J248/01

Mark Scheme

Question

Answer

Marks

(iv)

1
Use a larger conical flask
Use less sodium carbonate
Use less sulfuric acid
Use more sulfuric acid

✓

✓

17

June 2024
AO
element
3
...

Level 3 (5–6 marks)
Detailed description of physical properties of metals and
non-metals, correctly attributing metal properties to
section A and non-metal properties to section B
...

Contains properties extra to shiny and conducts
electricity
...
1
4 x 2
...
1 – Demonstrates knowledge and
understanding of structures and bonding
...

• Section B contains non-metals
...

AO2
...


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

Level 2 (3–4 marks)
Clear description of physical properties of metals and
non-metals, correctly attributing metal properties to
section A and non-metal properties to section B
...
The information presented is relevant and
supported by some evidence
...

There is an attempt at a logical structure with a line of
reasoning
...

0 marks
No response or no response worthy of credit
...

• Non-metals (or section B elements) are
dull, brittle
...

• Non-metals are poor conductors of
electricity and heat
...
1

2

2 x 1
...

ALLOW Group 1 elements will lose an electron to
form a full outer shell (of electrons)

✓

19

J248/01

Mark Scheme

Question

Answer
Seven

21 (a)
(b)

Marks

AO
element

1
3

2
...
1

✓

First check the answer on the answer line
If answer = 2
...
0 x 10-3 ÷ 1
...
1

✓

Any two from:

2

✓

No electrons are able to move to conduct electricity

(Form of carbon) X

2 x 1
...
p
...
4 x 107

June 2024

ALLOW has no delocalised electrons / no sea of
electrons
IGNORE free electrons / ions

✓
ALLOW electrons cannot move (through the
structure)
IGNORE electrons cannot carry the charge

✓

An electrode needs to conduct electricity

2

2 x 3
...
2

Guidance

J248/01

Mark Scheme

Question
22 (a)

(i)

Answer
First check the answer on the answer line
If answer = 7
...
5 ÷ 0
...
5
0
...
2=1

(ii)

Marks
2

June 2024
AO
Guidance
element
2 x 2
...


✓

✓
ALLOW 15:2 for 1 mark

As the surface area to volume ratio increases/gets larger,
the tablet will take less time to dissolve

✓

1

3
...
1b No mark for no; marks are for explanation
Answer must be comparative
ALLOW (Tablet D) has the highest / higher ratio

✓

So it will take less / least time to dissolve /
dissolves faster / fastest

✓

ALLOW Tablet D does not have smallest surface
area to volume ratio so will not dissolve slowest

✓

Tablet C will dissolve slowest as has smallest
surface area to volume ratio

22

✓

J248/01
(b)

Mark Scheme
(i)

(Use a) locating agent / stain / UV light

✓

1

June 2024
1
...
g
...
73 / 0
...
4÷6
...
73

1
...
2

✓
ALLOW ECF from incorrect distances
ALLOW 0
...
73

OR
distances moved = 4
...
0

✓

✓
Rf value = distance moved by spot /4
...
0
= 0
...
7 for 0
...
2 Any one correct = one mark
All three correct = two marks

Solution containing a
soluble solid dissolved
in a liquid

Three liquids with
different boiling points

✓✓
(b) (i)

Use a water bath (instead of the Bunsen burner) /
Use a heating mantle (instead of the Bunsen burner)

(ii)

1

✓

Add a thermometer (to the top of the flask containing the
mixture)

3
...
3b

ALLOW use an (electric) heater / heating plate
ALLOW idea of clamping the (round bottom) flask
(to prevent it falling over)
ALLOW use a temperature probe
DO NOT ALLOW thermometer added to collection
flask / receiving flask

24

J248/01

Mark Scheme

Question

Answer

2

AO
element
2 x 2
...
2

Marks

(c)

June 2024

Guidance

The empirical formula is CH2
...

The pure liquid contains two compounds
...

✓
The pure liquid will be a gas at above 35 °C
...
0 / 74 award 3 marks
4 x 12
...
0 OR 2 x 12
...
0
10 x 1
...
0 OR 5 x 1
...
0
✓

IGNORE any units given

✓

✓

(48
...
0 + 16
...
0

ALLOW ECF for addition of incorrect numbers of
C, H and O if no other mark awarded

25



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