OCR GCE Chemistry A H032/01: Breadth in chemistry AS LevelMark Scheme for June 2022
OCR GCE Chemistry A H032/01: Breadth in chemistry AS LevelMark
... [Show More] Scheme for June 2022
OCR GCE
Chemistry A
H032/01: Breadth in chemistry
AS Level
Mark Scheme for June 2022
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. OCR qualifications include AS/A Levels, Diplomas, GCSEs, Cambridge Nationals, Cambridge Technicals, Functional Skills, Key Skills, Entry Level qualifications, NVQs and vocational qualifications in areas such as IT, business, languages, teaching/training, administration and secretarial skills.
It is also responsible for developing new specifications to meet national requirements and the needs of students and teachers. OCR is a not-for-profit organisation; any surplus made is invested back into the establishment to help towards the development of qualifications and support, which keep pace with the changing needs of today’s society.
This mark scheme is published as an aid to teachers and students, to indicate the requirements of the examination. It shows the basis on which marks were awarded by examiners. It does not indicate the details of the discussions which took place at an examiners’ meeting before marking commenced.
All examiners are instructed that alternative correct answers and unexpected approaches in candidates’ scripts must be given marks that fairly reflect the relevant knowledge and skills demonstrated.
Mark schemes should be read in conjunction with the published question papers and the report on the examination.
© OCR 2022
Longer Answer Questions (requiring a developed response)
Where candidates have provided two (or more) responses to a medium or high tariff question which only required a single (developed) response and not crossed out the first response, then only the first response should be marked. 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.
6. Always check the pages (and additional objects if present) at the end of the response in case any answers have been continued there. If the candidate has continued an answer there, then add a tick to confirm that the work has been seen.
7. Award No Response (NR) if:
• there is nothing written in the answer space
Award Zero ‘0’ if:
• anything is written in the answer space and is not worthy of credit (this includes text and symbols).
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.
8. The RM Assessor comments box is used by your team leader to explain the marking of the practice responses. Please refer to these comments when checking your practice responses. Do not use the comments box for any other reason.
If you have any questions or comments for your team leader, use the phone, the RM Assessor messaging system, or e-mail.
9. Assistant Examiners will send a brief report on the performance of candidates to their Team Leader (Supervisor) via email by the end of the marking period. The report should contain notes on particular strengths displayed as well as common errors or weaknesses. Constructive criticism of the question paper/mark scheme is also appreciated.
10. For answers marked by levels of response: Not applicable in F501
a. To determine the level – start at the highest level and work down until you reach the level that matches the answer
b. To determine the mark within the level, consider the following
Descriptor Award mark
On the borderline of this level and the one
below At bottom of level
Just enough achievement on balance for this
level Above bottom and either below middle or at middle of level (depending on number of marks
available)
Meets the criteria but with some slight
inconsistency Above middle and either below top of level or at middle of level (depending on number of
marks available)
Consistently meets the criteria for this level At top of level
11. 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
Blank page
12. Abbreviations, annotations and conventions used in the detailed Mark Scheme (to include abbreviations and subject-specific conventions).
Annotation Meaning
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
13. Subject-specific Marking Instructions
INTRODUCTION
Your first task as an Examiner is to become thoroughly familiar with the material on which the examination depends. This material includes:
• the specification, especially the assessment objectives
• the question paper
• the mark scheme.
You should ensure that you have copies of these materials.
You should ensure also that you are familiar with the administrative procedures related to the marking process. These are set out in the OCR booklet Instructions for Examiners. If you are examining for the first time, please read carefully Appendix 5 Introduction to Script Marking: Notes for New Examiners.
Please ask for help or guidance whenever you need it. Your first point of contact is your Team Leader.
SECTION A
Question Answer Marks AO
element Guidance
1 B 1 AO1.1
2 A 1 AO1.1
3 D 1 AO1.1
4 C 1 AO2.1 ALLOW 7
5 D 1 AO1.2 ALLOW Ar
6 B 1 AO2.1
7 C 1 AO2.2
8 B 1 AO2.4
9 D 1 AO2.6
10 D 1 AO1.1
11 A 1 AO2.2
12 D 1 AO1.1
13 A 1 AO2.6
14 D 1 AO1.2 ALLOW 9
15 C 1 AO1.2 ALLOW 12
16 D 1 AO2.6
17 D 1 AO1.2
18 B 1 AO1.1
19 A 1 AO2.5
20 C 1 AO2.5
Total 20
SECTION B
Question Answer Marks AO
element Guidance
21 (a) (i) 3,3-dimethylbut-1-ene
CARE: Look for dimethyl 1 AO1.2
1 IGNORE lack of hyphens, or addition of commas or spaces
ALLOW full stops or spaces between numbers
e.g. 3.3 dimethyl but-1-ene
DO NOT ALLOW meth OR methy
(ii) ANNOTATE ANSWER WITH TICKS AND CROSSES 5
For curly arrows, ALLOW straight or snake-like arrows and small gaps (see examples):
1st curly arrow must
• go to a Br atom of Br–Br
AND
• start from, OR be traced back to any point across width of C=C
2nd curly arrow must
• start from, OR be traced back to, any part of
+Br–Br– bond
• AND go to Br –
1st curly arrow (from ANY alkene)
Curly arrow from double bond to Br of Br–Br
DO NOT ALLOW partial charge on C=C
AO1.2
2nd curly arrow
Correct dipole on Br–Br
AND curly arrow for breaking of Br–Br bond
AO1.2
Question Answer Marks AO
element Guidance
3rd curly arrow
Correct carbocation with + charge on C with 3 bonds
AND curly arrow from Br– to C+ of carbocation
DO NOT ALLOW δ+ on C of carbocation
OR
i.e. ALLOW carbonium + on either C atom
Correct product to match mechanism/intermediate
DO NOT ALLOW half headed or double headed arrows but allow ECF if seen more than once
Name of mechanism: Electrophilic addition IGNORE connectivity of CH3 groups in carbocation and product and ALLOW C4H9
AO2.5
3rd curly arrow must
• go to the C+ of carbocation
AND
• start from, OR be traced back to any point across width of lone pair on :Br–
• OR start from – charge on Br– ion
(Lone pair NOT needed if curly arrow shown from – charge on Br–)
AO2.5 ALLOW bromonium ion
ALLOW any combination of skeletal OR structural
OR displayed formula as long as unambiguous
NOTE: For a mechanism with HBr, ALLOW all marks EXCEPT for final product mark
AO1.1
(b) (i) 1 For repeat unit,
Question Answer Marks AO
element Guidance
• ‘side bonds’ required on either side of repeat unit from C atoms
• ALLOW more than one repeat unit
• ALLOW C4H9 for C(CH3)3
Correct polymer with side links 🗸
AO2.5
1 IGNORE brackets
• IGNORE n
IGNORE connectivity of C(CH3)3 group
(b) (ii) Advantage:
Energy/electricity (produced)
AND
Disadvantage:
CO2 produced
OR gases causing global warming/climate change
OR greenhouse gases, e.g CO2
BOTH advantage and disadvantage 1 AO1.1
1
ALLOW reduced use of fossil fuels
IGNORE produced CO2 and H2O
ALLOW less landfill / less harm to wildlife or environment (not just harmful)
ALLOW toxic/poisonous (waste) products/gases,
e.g. CO
IGNORE harmful/dangerous
Question Answer Marks AO
element Guidance
22 (a) FIRST CHECK ANSWER ON THE ANSWER LINE
IF answer = 190.47 (to 2 DP) award 2 marks
(188 12.13) + (189 16.75) + (190 27.23) + (192 43.89)
100
OR 190.4677 OR 190.468
= 190.47 (to 2 DP) 2 AO1.2
2
For 1 mark: ALLOW ECF to 2 DP if:
• %s used with wrong isotopes
ONCE
OR
• transposed decimal places for
ONE %
(b)
🗸
🗸
Mark by row 2 AO1.2
2
Easiest to check element first
ALLOW P3–
ALLOW names for elements
IGNORE charges with element in 1st column, even if wrong.
For electron configuration, ALLOW 4s2 before 3d8 i.e. 1s22s22p63s23p64s23d8
ALLOW upper case D, etc and subscripts,
e.g 4S23D1
ALLOW [Ar)3d84s2 [Show Less]