CPD - Edexcel

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Edexcel GCSE (9–1) Chemistry/Combined
Science Test Mark Scheme
Question
number
Answer
1a
An explanation linking the
following – 1 mark each.
1b
Acceptable answers
●
The temperature increases
as the solid is heated
because the particles are
gaining energy/moving
faster.
●
The temperature stays
constant while the solid is
melting.
●
The energy is used to
overcome the attractive
forces between the
particles.
●
In the liquid state, the
particles can slide over
each other.
Mark
(4)
Liquid
(1)
(Total for Question 1 = 5 marks)
Question
number
Answer
Acceptable answers
2a
2.3
(1)
2b
10
(1)
2c
A (Period) 2
(1)
2d
Mark
(2)
particle relative relative
mass
charge
electron
1
1837
-1
neutron
1
0/none/
neutral
proton
1
(+1)
4 correct: 2 marks
2 or 3 correct: 1 mark
0 or 1 correct: 0 marks
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1
GCSE Biology Test
Question
number
Answer
2e
Answer should include one idea
from each list.
Acceptable answers
Mark
(2)
Similarities
Both put:
●
elements into groups
/periods
●
elements with similar
properties in same group
●
metals and non-metals in
separately.
Differences
Mendeleev’s table:
●
was arranged by relative
atomic mass
Allow reverse argument for
modern periodic table.
●
had gaps
●
had fewer elements
Allow specific examples e.g.
germanium.
●
did not include the noble
gases.
(Total for Question 2 = 7 marks)
Question
number
Answer
3a
D a salt and water only
(1)
3bi
A description including two of
the following.
(2)
3 b ii
3 b iii
Acceptable answers
●
(acid) colourless
(liquid/solution)
Ignore clear.
●
(carbonate) green (solid)
disappears
Allow dissolves.
●
effervesces/fizzes/bubbles
●
blue/green (solution)
(forms)
Ignore gas/carbon dioxide
given off.
A description including the
following.
●
Dilter (to remove the
excess copper carbonate).
(1)
●
Evaporate some/half of the
water (from the filtrate)
then leave to cool. (1)
(2)
Allow leave the water to
evaporate slowly.
CuCO3 + 2HCl  CuCl2 + CO2 + H2O
●
Correct reactants (1)
●
Correct products (1)
Mark
(3)
Balancing correct formulae (1)
(Total for Question 3 = 8 marks)
2
© Pearson Education Ltd 2015. Copying permitted for purchasing institution only. This material is not copyright free.
GCSE Biology Test
Question
number
Answer
4a
A description including any two
from:
4b
4c
Acceptable answers
(2)
●
floats
●
moves (around)
●
effervescence/fizzing/
bubbles
Allow white smoke formed.
●
melts/changes to a ball
shape
Allow dissolve/explodes.
●
becomes smaller
/disappears.
Allow moves (around) on the
surface.(2)
Ignore gas/hydrogen given off.
Ignore burns/catches fire/
ignites/flame/sparks.
Ignore addition of indicators.
2Na + 2H2O  2NaOH + H2
●
All 3 balancing numbers
correct = 2 marks.
●
1 or 2 correct = 1 mark.
Mark
Indicative content
(2)
(6)
An explanation including some of the following points.
Reactivity series
●
Aluminium more reactive than iron/aluminium higher than
iron in reactivity series.
●
Aluminium forms stronger bonds with oxygen than iron does.
●
Aluminium oxide more stable (to decomposition) than iron
oxide.
●
Aluminium more reactive than carbon/aluminium higher than
carbon in reactivity series.
Cost
●
Electrolysis/electricity (more) expensive (than heating with
carbon).
●
Heating with carbon is (relatively) cheap method.
Iron
●
Carbon more reactive than iron/iron less reactive than
carbon.
●
Iron oxide reduced by heating with carbon.
●
No need to use (expensive) electrolysis.
Aluminium
●
Aluminium oxide difficult to reduce.
●
Aluminium oxide cannot be reduced by (heating with)
carbon.
●
(Cheaper) reduction with carbon does not work.
●
Need more powerful method of reduction.
●
Therefore must use electrolysis.
© Pearson Education Ltd 2015. Copying permitted for purchasing institution only. This material is not copyright free.
3
GCSE Biology Test
Question
number
Answer
Acceptable answers
Mark
No rewardable content = 0 marks
Level 1: 1–2 marks
●
A limited description e.g. aluminium extracted by
electrolysis.
●
The answer communicates ideas using simple language and
uses limited scientific terminology.
●
Spelling, punctuation and grammar are used with limited
accuracy.
Level 2: 3–4 marks
●
A simple description containing two statements referring to
one.
●
Method of extraction and a cost e.g. iron is extracted by
heating.
●
Iron oxide with carbon and this is cheaper.
●
or The relative reactivity of one metal and a method of
extraction e.g. aluminium is extracted by electrolysis.
Aluminium is more reactive than iron (has made a
comparison in reactivity).
●
or The relative reactivity of one metal and reference to cost
e.g. aluminium is a more reactive metal and so is expensive
to extract.
●
The answer communicates ideas showing some evidence of
clarity and organisation and uses scientific terminology
appropriately.
●
Spelling, punctuation and grammar are used with some
accuracy.
Level 3: 5–6 marks
●
A detailed description containing at least three statements
referring to relative reactivity of both metals, a method of
extraction of at least one metal, and a cost reference e.g.
aluminium is more reactive than iron so is extracted by
electrolysis which is expensive.
●
The answer communicates ideas clearly and coherently uses
a range of scientific terminology accurately.
●
Spelling, punctuation and grammar are used with few errors.
(Total for Question 4 = 10 marks)
TOTAL FOR PAPER = 30 MARKS
4
© Pearson Education Ltd 2015. Copying permitted for purchasing institution only. This material is not copyright free.
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