Twent - Study guides, Class notes & Summaries
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OCR GCSE Chemistry B Paper 1 Foundation tier Twenty First Century Science (J258/01) Mark Scheme for June 2023
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GCSE 
 
Chemisty B Twenty First Century Science 
 
: Breadth in Chemistry (Foundation Tier) 
 
General Certificate of Secondary Education 
 
 
Mark Scheme for June 2023
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OCR 2023 GCSE Combined Science B Twenty First Century Science J260/08: Combined science (Higher Tier) Question Paper & Mark Scheme (Merged
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© OCR 2023 
0.0 cm 
A The tester lets go of the ruler. 
B The participant catches the ruler as soon as they realise the tester has let go of the 
ruler. 
C The distance the ruler has dropped is measured. 
D The participant has their fingers and thumb near, but not touching, the ruler. 
E The tester holds a ruler above the participant’s hand. 
1 Two students are doing an experiment to investigate reaction times. The diagram shows their 
experiment. 
Tester 
Participant 
(a) The statements...
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OCR 2023 GCSE Combined Science B Twenty First Century Science J260/02: Chemistry (Foundation Tier) Question Paper & Mark Scheme (Merged)
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1 The diagram shows part of Mendeleev’s Periodic Table. 
B 
11 
C 
12 
N 
14 
O 
16 
F 
19 
Al 
27 
Si 
28 
P 
31 
S 
32 
Cl 
35.5 
As 
75 
Se 
79 
Br 
80 
In 
115 
Sn 
119 
Sb 
122 
Te 
128 
I 
127 
(a) Give the symbols of the two elements shown in the diagram which are not in order of atomic 
mass. 
........................................................... and ........................................................... [1] 
(b) Mendeleev left gaps for elements that had not ...
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OCR 2023 GCSE Combined Science B Twenty First Century Science J260/01: Biology (Foundation Tier) Question Paper & Mark Scheme (Merged)
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© OCR 2023 
Chemical Bacteria in the gut compete 
against pathogens 
Microbial Skin stops pathogens 
entering the body 
Physical Stomach acid 
destroys pathogens 
1 Some bacteria are pathogens that cause diseases. 
(a) Our blood contains white blood cells. They help protect us against pathogens. 
(i) Write down the name of the organ that pumps the blood around our body. 
.............................................................................................................................
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OCR 2023 GCSE CHEMISTRY B TWENTY FIRST CENTURY SCIENCE J258/03: BREADTH IN CHEMISTRY (HIGHER TIER) QUESTION PAPER & MARK SCHEME (MERGED
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1 Argon forms 1% of the air and is unreactive. 
Argon is used as a replacement for nitrogen when nitrogen is too reactive. 
(a) Argon is unreactive because it is in Group 0 of the Periodic Table. 
State one other property of argon. 
.............................................................................................................................................. [1] 
(b) Chlorine is very reactive. Argon is unreactive. 
Explain how the reactivity of these two elements a...
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OCR 2023 GCSE Biology B Twenty First Century Science J257/02: Depth in Biology (Foundation Tier) Question Paper & Mark Scheme (Merged)
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© OCR 2023 
ring 
ring 
ring 
1 Fig. 1.1 shows parts of the human nervous system. 
Fig. 1.1 
Brain 
Structure B 
Muscle 
Spinal cord 
Structure A 
(a) Structure A allows us to sense the things we touch. 
What is the name of structure A? 
Put a around the correct option. 
CNS Effector Motor neuron Sensory neuron [1] 
(b) The muscle contracts to move the arm when it receives a nerve impulse from the brain. 
What type of structure is the muscle? 
Put a around the correct option. 
CNS Effector M...
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OCR 2023 GCSE CHEMISTRY B TWENTY FIRST CENTURY SCIENCE J258/02: DEPTH IN CHEMISTRY (FOUNDATION TIER) QUESTION PAPER & MARK SCHEME (MERGED)
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1 Poly(ethene) is a polymer which forms when ethene monomers react together in an addition 
polymerisation reaction. 
The structure of an ethene monomer and the repeating unit of poly(ethene) are shown in 
Fig. 1.1. 
Fig. 1.1 
H H H H 
C C C C 
H H H H 
Ethene monomer Repeating unit of poly(ethene) 
(a) Which statements are true only for an ethene monomer, which are true only for the 
repeating unit of poly(ethene) and which are true for both? 
Tick () one box in each row. 
Tru...
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OCR 2023 GCSE Biology B Twenty First Century Science J257/01: Breadth in Biology (Foundation Tier) Question Paper & Mark Scheme (Merged
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© OCR 2023 Turn over 
"The larger the animal, the more chromosomes it has in each body cell." 
1 (a) Write these structures in order of size. 
Cell Chromosome Gene Nucleotide Nucleus 
Smallest ..................................... 
..................................... 
..................................... 
..................................... 
Largest ..................................... [4] 
(b) The table shows the number of chromosomes that different animals have in each body cell. 
...
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OCR 2023 GCSE Physics B Twenty First Century Science J259/01: Breadth in physics (Foundation Tier) Question Paper & Mark Scheme (Merged)
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2 
© OCR 2023 
Water in 
a reservoir 
Pipe 
Turbine 
National grid 
Generator 
1 The diagram shows a hydroelectric power station. 
(a) What is the useful energy store of the water in the reservoir? 
Tick () one box. 
Chemical 
Electrical 
Gravitational Potential 
Thermal 
[1] 
(b) Many of the main energy resources use a turbine attached to a generator. 
Complete the table to state what drives the turbine for each energy resource. 
Tick () one box in each row. 
What drives the turbine 
Water Win...
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OCR 2023 GCSE Combined Science B Twenty First Century Science J260/04: Combined science (Foundation Tier) Question Paper & Mark Scheme (Merged)
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2 
© OCR 2023 
Stomach acid Clots the blood to prevent 
pathogens from entering cuts 
Skin Produces antibodies, or ingests 
and digests pathogens 
Platelet Barrier that prevents pathogens 
from entering the body 
White blood cell Can kill pathogens and stop 
them from reproducing 
1 Pathogens can cause diseases in humans. 
Draw lines to connect each defence mechanism with the explanation of how it functions. 
Defence mechanism Explanation 
[3] 
3 
© OCR 2023 Turn over 
2 (a) The plant geno...
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