Oxford Revise AQA GCSE Combined Science Foundation | Chapter C5 answers
C5: Quantitative chemistry
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Question |
Answers |
Extra information |
Mark |
AO / Specification reference |
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01.1 |
six water molecules react with six carbon dioxide molecules |
1 |
AO1 5.3.1.1 |
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01.2 |
(l) (g) |
1 1 |
AO1 5.2.2.2 |
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01.3 |
18 |
1 |
AO2 5.3.1.1 |
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01.4 |
the same no conservation |
1 1 1 |
AO1 5.3.1.1 |
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02.1 |
2Mg + O2 → 2MgO |
one mark for balancing one mark for oxygen one mark for state symbol |
3 |
AO1 AO2 5.2.2.2 5.3.1.1 |
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02.2 |
oxygen atoms bond with the magnesium atoms to form solid magnesium oxide so the product/magnesium oxide has more particles/more matter than starting magnesium/oxygen has mass so heavier |
1 1 |
AO2 5.3.1.3 |
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02.3 |
Mg ion and O ion are drawn with 1 shell each. Mg ion has 8 dot and is inside square brackets with a superscript 2+ to the right of the bracket O ion is drawn with 6 crosses and 2 dots and is inside square brackets with a superscript 2- to the right of the bracket |
one mark for magnesium electron structure one mark for oxygen electron structure one mark for charges |
3 |
AO2 5.2.1.2 |
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03.1 |
2Li + 2HCl → 2LiCl + H2 |
2 |
AO2 5.3.1.1 |
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03.2 |
LiCl(aq) |
1 |
AO2 5.2.2.2 |
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03.3 |
hydrogen chloride |
1 |
AO1 5.3.2.5 |
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03.4 |
\( \begin{align} & 500\ \textrm{cm}^3 = 0.5\ \textrm{dm}^3\\ & \frac{7.3}{0.5}\\ & = 14.6\ \textrm{g/dm}^3 \end{align} \) |
error carried forward |
1 1 1 |
AO1 AO2 5.3.2.5 |
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03.4 |
mass decreases because gas produced that escapes from the reaction flask |
1 1 |
AO2 AO3 5.3.1.3 |
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04.1 |
Zn + 2HCl → ZnCl2 + H2 |
1 |
AO2 5.3.1.1 |
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04.2 |
3.25 + 3.65 = 6.9 g |
1 |
AO1 5.3.1.1 |
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04.3 |
(1 × 2) + 32 + (16 × 4) = 98 |
1 1 |
AO1 AO2 5.3.1.2 |
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05.1 |
50 cm3 |
1 |
AO2 |
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05.2 |
48 to 56 |
1 |
AO3 5.3.1.4 |
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05.3 |
mean ± 4 |
1 |
AO3 5.3.1.4 |
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06.1 |
three oxygen atoms |
1 |
AO2 5.3.1.1 |
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06.2 |
32 + (16 × 2) = 64 |
1 |
AO1 5.3.1.2 |
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06.3 |
1.62 – 1.28 = 0.34 g |
1 |
AO2 5.3.1.1 |
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07.1 |
(aq) – aqueous – 2nd image (g) – gas – 3rd image (s) – solid – 1st image (l) – liquid – 3rd image |
one mark for one correct two marks for two correct three marks for all correct |
3 |
AO1 5.2.2.2 |
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07.2 |
(s) + (aq) → (g) + (aq) |
one mark for two correct two marks for all correct |
2 |
AO2 5.2.2.2 |
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07.3 |
95 |
1 |
AO1 5.3.1.2 |
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07.4 |
19 × 0.5 = 9.5g |
1 |
AO1 5.3.2.5 |
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07.5 |
decreased gas |
1 1 |
AO1 AO2 5.3.1.3 |
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08.1 |
decreased gas |
1 |
AO1 5.1.1.5 |
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08.2 |
25 protons 30 neutrons |
1 1 |
AO1 AO2 5.3.1.2 |
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08.3 |
ionic |
1 |
AO2 5.1.2.5 |
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09.1 |
14 |
1 |
AO3 5.3.1.4 |
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09.2 |
14 cm3 = 0.014 dm3 10 × 0.014 = 0.14 g |
1 1 1 |
AO2 5.3.2.5 |
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09.3 |
10 cm3 closest to volume being measured most accurate |
1 1 1 |
AO3 5.3.1.4 |
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10.1 |
one from:
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accept any other reasonable answer |
1 |
AO3 5.1.2.5 |
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10.2 |
2Na + Cl2 → 2NaCl |
one mark for products one mark for reactants |
1 1 |
AO2 5.3.1.1 |
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10.3 |
a solid substance that dissolved in a liquid |
1 |
AO1 5.3.2.5 |
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10.4 |
450 cm3 = 0.45 dm3 29.3 × 0.45 = 13.14 g |
1 1 1 |
AO1 AO2 5.3.2.5 |
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10.5 |
+/- 0.01 |
1 |
AO3 5.3.1.4 |
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10.6 |
Level 3: The description is detailed and accurate. The writing is clear, coherent and logical. |
5-6 |
AO1 5.2.1.2 5.2.1.3 |
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Level 2: The description is correct, although lacks detail. The writing is mainly clear, although the structure may lack logic. |
3-4 |
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Level 1: Some aspects of the description are correct. The writing lacks clarity, coherence and logic. |
1-2 |
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No relevant content. |
0 |
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Indicative content:
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