Mark Scheme. September Pearson BTEC Level 3 Applied Science. Unit 5: Principles and Applications of Science II

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1 Mark Scheme September 2017 Pearson BTEC Level 3 Applied Science Unit 5: Principles and Applications of Science II

2 Edexcel and BTEC Qualifications Edexcel and BTEC qualifications come from Pearson, the world s leading learning company. We provide a wide range of qualifications including academic, vocational, occupational and specific programmes for employers. For further information visit our qualifications websites at or for our BTEC qualifications. Alternatively, you can get in touch with us using the details on our contact us page at If you have any subject specific questions about this specification that require the help of a subject specialist, you can speak directly to the subject team at Pearson. Their contact details can be found on this link: You can also use our online Ask the Expert service at You will need an Edexcel username and password to access this service. Pearson: helping people progress, everywhere Our aim is to help everyone progress in their lives through education. We believe in every kind of learning, for all kinds of people, wherever they are in the world. We ve been involved in education for over 150 years, and by working across 70 countries, in 100 languages, we have built an international reputation for our commitment to high standards and raising achievement through innovation in education. Find out more about how we can help you and your students at: September 2017 Publications Code xxxxxxxx* All the material in this publication is copyright Pearson Education Ltd 2017

3 Unit 5: Applications of Science II sample mark scheme General marking guidance All learners must receive the same treatment. Examiners must mark the first learner in exactly the same way as they mark the last. Marking grids should be applied positively. Learners must be rewarded for what they have shown they can do, rather than be penalised for omissions. Examiners should mark according to the marking grid, not according to their perception of where the grade boundaries may lie. All marks on the marking grid should be used appropriately. All the marks on the marking grid are designed to be awarded. Examiners should always award full marks if deserved. Examiners should also be prepared to award zero marks, if the learner s response is not rewardable according to the marking grid. Where judgement is required, a marking grid will provide the principles by which marks will be awarded. When examiners are in doubt regarding the application of the marking grid to a learner s response, a senior examiner should be consulted. Specific marking guidance The marking grids have been designed to assess learner work holistically. Rows in the grids identify the assessment focus/outcome being targeted. When using a marking grid, the best fit approach should be used. Examiners should first make a holistic judgement on which band most closely matches the learner s response and place it within that band. Learners will be placed in the band that best describes their answer. The mark awarded within the band will be decided based on the quality of the answer, in response to the assessment focus/outcome and will be modified according to how securely all bullet points are displayed at that band. Marks will be awarded towards the top or bottom of that band, depending on how they have evidenced each of the descriptor bullet points.

4 Question 1(a) Answer X aorta Additional guidance Ignore artery Mark 2 1(b) Y pulmonary vein substitution (1) 70 x alone gains full marks 2 evaluation (1) (c)(i) P 1 1(c)(ii) T 1 1(c)(iii) the time taken for the impulse to travel from the atria to ventricles (1) through the atrioventricular node, bundle of His, to {Purkinje/Purkyne} fibres (1) 2 Total marks = 8 marks

5 Question Answer Additional Mark guidance 2(a) phospholipid bilayer 1 2(b) (the movement of) ions/molecules/solutes (across a cell membrane) (1) using a carrier protein (1) Accept a named example, e.g. amino acid 4 against a concentration gradient (1) using ATP (1) 2(c) both simple and facilitated diffusion occurs down the concentration gradient (1) ATPassociated channel protein gains two marks as an alternative to the second and fourth marking point 3 facilitated diffusion requires channel proteins (whereas simple diffusion doesn t) / ORA (1) (Line B flattens because) rate of entry becomes constant when protein channels become saturated (whereas Line A continues) /ORA(1) Total marks = 8 marks

6 Question Answer Additional Mark guidance 3(a) carbon dioxide / water vapour (1) 1 3(b) 4 thin (surface) / flattened/ squamous epithelium (1) give a short diffusion pathway (1) moisture contains surfactant (1) which stops collapse/reduces surface tension in the alveoli walls (1) 3(c) substitution (1) 0.5 x 12 Other info: 6 breaths in 30 secs so 12 in one minute 2 3(d) evaluation (1) 6 Any two from Increased energy requirements (1) 6 alone gains all 2 marks 3 Increased demand for carbon dioxide removal (1) Increased demand for oxygen intake (1) AND Increase in rate of ATP production/aerobic respiration Total marks = 10 marks

7 Question 4(a) Answer Additional guidance Mark ADH controls reabsorption of water (from the filtrate in the kidneys) (1) 4 drug X inhibits/reduces the release of ADH (1) less water reabsorbed / more water is lost in urine (1) causing urine to become less concentrated/ more dilute (1) 4 (b) protein molecules are large (1) 4 cannot cross the membrane (from the blood plasma into the filtrate) (1) glucose is filtered from the plasma (1) but is all reabsorbed in the proximal convoluted tubule (1) Total marks = 8 marks

8 Question Indicative content number 5 Answers will be credited according to the learner s demonstration of knowledge and understanding of the material, using the indicative content and levels descriptors below. The indicative content that follows is not prescriptive. Answers may cover some or all of the indicative content but learners should be rewarded for other relevant answers. Indicative content ABO blood type system blood is typed, or classified, according to the presence or absence of certain markers (antigens) antigens are found on (the cell surface membranes of) red blood cells antigens on each type of blood are different O has no antigens AB has both types of antigen A has A antigens, B has B antigens antigens allow your immune system to recognise self Group A has antibodies in the plasma against B antigens Group B has antibodies in the plasma against A antigens Group O has antibodies in the plasma against A and B antigens Group AB has no antibodies in the plasma against A or B antigens Importance in blood transfusions mismatches with the ABO blood types cause {transfusion reactions/ clumping of red blood cells} transfusion reactions are (sometimes) life-threatening e.g. The anti-b antibodies in a group A recipient dock with the B antigens on group B red blood cells and {coagulate/clump} the red blood cells type O blood can be given to people with any of the ABO types people with type AB blood are called universal recipients type AB blood does not have anti-a or anti-b antibodies type AB blood does not produce anti-a or anti-b antibodies

9 Mark scheme (award up to 6 marks) refer to the guidance on the cover of this document for how to apply levels-based mark schemes*. Level Mark Descriptor 0 No awardable content Level Demonstrates adequate knowledge and understanding of scientific facts/concepts to the given context with generalised comments made Generic statements may be presented rather than linkages to the context being made so that lines of reasoning are unsupported or partially supported The comparison will contain some similarities and differences showing some structure and coherence Level Demonstrates good knowledge and understanding by selecting and applying some relevant scientific facts/concepts to provide the comparison being presented Lines of argument mostly supported through the application of relevant evidence drawn from the context Demonstrate an awareness of both similarities and differences leading to a comparison which has a structure which is mostly clear, coherent and logical Level Demonstrates comprehensive knowledge and understanding by selecting and applying relevant knowledge of scientific facts/concepts to provide the comparison being presented Line(s) of argument consistently supported throughout by sustained application of relevant evidence drawn from the context The comparison shows a logical chain of reasoning which is supported throughout by sustained application of relevant evidence

7(c) Step 1 4 Step 2 Reject Br +/ Br - once only for first two marking points Correct partial charges on bromine and curly arrow from double

10 Section B Properties and Uses of Substances Question Answer Additi onal Guida nce 6(a) Neutralisation 1 6(b) Ca(OH)2 + 2HCl CaCl2 + 2H2O 3 LHS (1) RHS (1) Balancing of correct formula (1) Mark Total marks = 4 marks Question Answer Additional Mark Guidance 7(a) A CH 3 1 7(b) B H + 1 7(c) Step 1 4 Step 2 Reject Br +/ Br - once only for first two marking points Correct partial charges on bromine and curly arrow from double bond to Br δ+ (1) Curly arrow from bromine bond to Br δ- (1) Carbocation as in diagram (1) Curly arrow from Br - to C + (1) Total marks = 6 marks

Question Answer Additional Mark Guidance 8(a) C12H26 1 8(b) 1 8(c) As the number of carbon atoms increases / size of the molecule increases, the boiling point increases (1) 2

mark for drawn and labelled sigma bond. 1 mark for drawn and labelled pi bond both lobes (above and below) the carbon atoms must be identified as the pi bond.

11 Question Answer Additional Mark Guidance 8(a) C12H26 1 8(b) 1 8(c) As the number of carbon atoms increases / size of the molecule increases, the boiling point increases (1) 2 This is because there is a greater density of electrons / there are more electrons, which create stronger {intermolecular/van der Waals} forces between molecules (1) 8(d) 2 1 mark for drawn and labelled sigma bond. 1 mark for drawn and labelled pi bond both lobes (above and below) the carbon atoms must be identified as the pi bond. 8(e) Ignore misnaming of isomers 3 (cis but-2-ene) Accept CH3 in place of a displayed methyl group (trans but-2-ene) 1 mark for double bond in correct position (between 2 nd and 3 rd carbons) in diagrams.

12 1 mark for structural formula (of cis isomer) with both CH3 groups / H atoms on same side of double bond. 1 mark for structural formula (of trans isomer) with both CH3 groups / H atoms on opposite sides of double bond. Total marks = 9 marks

13 Question 9(a)(i) Answer (The standard enthalpy change of formation is) the enthalpy change when one mole of compound / substance (1) Additional Guidance Mark 2 is formed from its elements under standard conditions / conditions of 298 K and 1 atm (1) 9(a)(ii) Calculation of 2 mols of H2 : 2 x = (1) ECF (max 3 marks) 4 Reversal of enthalpy of combustion of methane in equation: = (+) (1) (max 3 marks) Substitution of values: (1) Incorrect substitution (max 3 marks) Evaluation: -75 (1) 9(b) -75 with no working gains 4 marks Temperature change calculated: = 12K (1) ECF 3 Substitution: 5 x 4.18 x 12 (1) Evaluation: (1) with no working gains 3 marks Total marks = 9 marks

14 Question 10(a) Answer Physical property: Retains strength / does not melt at high temperature (1) Additional Guidance Mark 2 10(b)(i) 10(b)(ii) Chemical property: Chemically stable / does not decompose / does not burn / combust at high temperature (1) To allow the ions to move / to make the ions mobile (1) The ions can then carry the electrical current during electrolysis (1) Any two from: Do not accept electrons / atoms / particles 2 2 Large amounts of energy required to maintain a high temperature (to melt / dissolve the alumina) (1) Large amounts of electricity required (for electrolysis) (1) Graphite anodes need to be replaced regularly (1)

15 Question Indicative content number 10(c) brine is sodium chloride solution brine/sodium chloride solution contains: o sodium ions (Na + ) o chloride ions (Cl - ) o hydrogen ions (H + ) o hydroxide ions (OH - ) ions are free to move in solution and carry electric charge / current negative chloride ions are attracted to the positive anode positive hydrogen ions are attracted to the negative cathode chlorine gas (Cl2) formed at the anode 2Cl - Cl2 + 2e- hydrogen gas (H2) formed at the cathode 2H + + 2e - H2 Na + and OH - ions are left in solution / sodium hydroxide is left hydrogen can react with chlorine to form HCl chlorine and hydrogen are separated by the diaphragm / extracted off separately so they do not react together sodium hydroxide and chlorine can react together to form sodium chlorate / bleach diaphragm separates sodium hydroxide from chlorine so that they do not react together Mark scheme (award up to 6 marks) refer to the guidance on the cover of this document for how to apply levels-based mark schemes*. Level Mark Descriptor 0 No rewardable material. Level Demonstrates adequate knowledge of scientific facts/concepts with generalised comments made. Generic statements may be presented rather than linkages being made so that lines of reasoning are unsupported or partially supported. The explanation shows some structure and coherence. Level Demonstrates good knowledge and understanding by selecting and applying some relevant scientific knowledge facts/concepts to provide the discussion being presented. Lines of argument mostly supported through the application of relevant evidence. The explanation shows a structure which is mostly clear, coherent and logical. Level Demonstrates comprehensive knowledge and understanding by selecting and applying relevant knowledge of scientific facts/concepts to provide the discussion being presented. Line(s) of argument consistently supported throughout by sustained application of relevant evidence. The explanation shows a well-developed structure which is clear, coherent and logical

16 Section C Thermal Physics, Materials and Fluids Question Answer Additional guidance Mark 11(a)(i) nothing 1 11(a)(ii) D Z 1 11(a)(iii) Y (1) (section must be horizontal as) there is no temperature increase at change of state (1) it must be Y because boiling occurs at a higher temperature than melting (1) 3 11(b) lead balls at the top of the tube have a greater gravitational potential energy (GPE) (1) Ignore sound 4 as the lead balls fall the GPE is converted to kinetic energy (KE) (1) when the lead balls collide with each other the KE is transferred from one lead ball to another (1) increase in the lead balls KE results in an increase in temperature/average KE of particles increases (1) Total marks = 9 marks

17 Question Answer Additional guidance Mark 12(a) 1 D 12(b) pressure difference produces an upward force (1) 3 the curve on the top of the wing causes low pressure air (1) the flat underwing causes high pressure air (1) Total marks = 4 marks

18 Question Answer Additional guidance Mark 13(a) (an expansion that) happens at a constant temperature. 1 13(b) substitution (1) 1.20 x 10 6 x 3.00 x 10-4 = 3.00 x x 1.38 x T rearrangement (1) T = 1.20 x 10 6 x 3.00 x x x 1.38 x evaluation (1) K Substitution and rearrangeme nt in either order Allow equation in words or symbols 3 13(c) the gas needs energy to expand (1) the expanding gas does work on the surrounding air (1) the energy to do this comes from the internal energy of the gas (so the temperature drops) (1) 870K Pushes the air away 3 Total marks = 7 marks

19 Question Answer Additional guidance Mark 14(a) conversion of 400 C and 25 C to K (1) 673 and alone gains three marks 3 substitution (1) = efficiency 673 evaluation (1) 0.56 If temperature is not converted to Kelvin, accept for two marks 56% 14(b) refrigerant liquid (expands and) turns into a gas as it enters the refrigerator (1) it takes in latent heat from the content of the refrigerator (1) in the compressor the gas turns into a liquid (1) it releases latent heat to the surroundings (1) Penalise once only if latent heat not mentioned in marking points 2 and 4 4 Total marks = 7 marks

20 Question Answer Additional guidance Mark 15(a) substitution (1) = 1788 volume rearrangement (1) 1788 = volume 7870 evaluation (1) m 3 15(b) ductile is the ability to deform under tensile stress (1) which means it can be drawn (into wires) when pulled (1) malleable is the ability to deform under compressive stress (1) which means it can be hammered into shape (1) 4

21 Question number 15(c) Indicative content Young s modulus Mild steel has a higher value of E than cast iron/ora. Because mild steel has a high value of E it is more flexible/ora. A high Young s modulus means higher strength. Density For a same size beam, mild steel is heavier/ora because it has a high density/ora. Brittleness If a material is brittle it will snap. Mild steel is less brittle than cast iron/ora. Conclusion Support beams need to be strong and unlikely to snap. Support beams higher up in the building add to the weight overall. Support beams at the bottom of the building need to take the weight of the building, including the beams at the top. Mild steel Mild steel is better because it is stronger; it is less likely to snap, even though it is heavier for the same size beam. It will need more support to take the weight of the beams because it is heavier. Cast iron Cast Iron is worse because it is not as strong; it is more likely to snap. Its lower density is an advantage because the weight of the beams will be lower so they will need less support. It would fail more easily than steel but is more flexible than concrete. It is denser than concrete so would require more support. Mark scheme (award up to 6 marks) refer to the guidance on the cover of this document for how to apply levels-based mark schemes*. Level Mark Descriptor 0 No rewardable material.

22 Level 1 Adequate interpretation, analysis and/or evaluation of the scientific information with generalised comments being made. Generic statements may be presented rather than linkages being made so that lines of reasoning are unsupported or partially supported. The discussion shows some structure and coherence. Level 2 Good analysis, interpretation and/or evaluation of the scientific information. Lines of argument mostly supported through the application of relevant evidence. The discussion shows a structure which is mostly clear, coherent and logical. Level 3 Comprehensive analysis, interpretation and/or evaluation of all pieces of scientific information. Line(s) of argument consistently supported throughout by sustained application of relevant evidence. The discussion shows a well-developed structure which is clear, coherent and logical. For more information on Edexcel qualifications, please visit our website Pearson Education Limited. Registered company number with its registered office at Edinburgh Gate, Harlow, Essex CM20 2JE

Mark Scheme (Results) Summer BTEC Level 1/Level 2 Firsts in Applied Science. Unit 8: Scientific Skills (20474E)

Mark Scheme (Results) Summer BTEC Level 1/Level 2 Firsts in Applied Science. Unit 8: Scientific Skills (20474E) Mark Scheme (Results) Summer 2017 BTEC Level 1/Level 2 Firsts in Applied Science Unit 8: Scientific Skills (20474E) Edexcel and BTEC Qualifications Edexcel and BTEC qualifications come from Pearson, the