CBSE Science Class 10 Item Bank PDF

CBSE Competency-based education for CBSE Item Bank: Science Class 10 September 2021 Content created by Introduction for teachers A bank of resources has been created to support teachers to develop and administer end-of- class tests. These resources should be used...

CBSE Competency-based education for CBSE Item Bank: Science Class 10 September 2021 Content created by Introduction for teachers A bank of resources has been created to support teachers to develop and administer end-of- class tests. These resources should be used together. You can view and download the following resources from http://cbseacademic.nic.in: Learning ladder for science Assessment specification for science Sample lesson plans This document is a compilation of the sample items for Science Class 10. There are 78 items. This item bank is supported by the assessment specification which sets out the end-of-class assessment requirements and the learning ladder for the subject which maps the CBSE syllabi content to the NCERT curriculum. The item index (page 6) shows how each item maps to the learning ladder content and the assessment objectives. What these assessment items can be used for You can use the bank of questions in whatever way you wish but three main purposes have been identified: Create end-of-class assessments using the items from the bank to meet the requirements set out in the assessment specifications. Create end-of-topic tests using the items from the bank for when you finish teaching a topic. Use individual or groups of questions from the bank to create or add to worksheets for use in class and for homework. What is in this document You will find linked questions and single questions which cover different aspects of the learning ladder content and different assessment objectives. You can use these questions to create your own assessments. Each item in this document begins with the metadata (see Figure 1). The metadata gives details of the content, assessment objective coverage and the number of marks. There is then a section showing any source material needed followed by the questions themselves and finally the mark scheme for the questions. www.britishcouncil.org 2  Item identity AO1 AO2 AO3 AO4 Content Marks marks Reference(s) Marks marks marks Science10TM2 1 10.3.22 Identify the relationships 1 between current, potential difference, resistance and power. Figure 1: Example of metadata How to use the assessment items You can peruse the bank of items by flicking through this document and selecting questions you wish to use. However, if you are assessing specific content then you can use the learning ladder to identify this content and then use the item index (page 6) to find any items which cover that content. Please note that not all of the content will have items. The item bank is only a sample of the questions which could be created so it may be necessary for you to write questions of your own to fill gaps. When you find a relevant assessment item in this document, you can copy and paste the question(s) and any source material into a new Word document which will form the assessment or worksheet. Other questions from the bank can be copied and pasted to this document and an assessment or worksheet covering a range of items created. The questions can then easily be edited in the new document using Word and you can add any questions you write to best meet the needs of your classes. Once the questions have been pasted into the new document the numbering of the items can be changed so that they run through 1, 2 etc. There should be no need to change the numbering of parts (a), (b) etc unless a question has been deleted. You can create the mark schemes in the same way by copying the relevant section of the item documents and pasting them into a separate Word document which will form the mark scheme. Again, the question numbering will need to be amended. You can use these mark schemes to make sure that the marking is standardised, particularly if more than one teacher uses the assessment. When creating an end-of-class test the teacher should use the assessment specification to identify the number of marks and questions needed, the balance of content to be covered and the weighting of the assessment objectives needed. You can then select items from the bank to build a test that meets the assessment specification and then order these in a logical manner so that it allows the students to work through the assessment. You should also add a front page www.britishcouncil.org 3 with the assessment name and details of the number of marks and the length of the assessment. Again, the mark scheme can be created at the same time and question numbers will need to be amended. When copying items from the bank care needs to be taken to keep the format and style of the items consistent including the spacing and layout and ensuring that the number of marks available for each question is clearly linked to the question. www.britishcouncil.org 4 Assessment objectives This document sets out the assessment objectives for CBSE Science and their percentage weighting for the CBSE end of year tests for the different classes from VI to X. Class No. Description of Assessment Objective VI VII VIII IX X AO1 Demonstrate knowledge and understanding of 40 40 40 30 30 scientific ideas, techniques, and procedures. AO2 Apply knowledge and understanding of scientific ideas, techniques and procedures to classroom 40 40 40 30 30 and real-world situations AO3 Analyse scientific information and ideas to present data and interpret patterns and 10 10 10 20 20 relationships AO4 Evaluate scientific information to: make judgments and draw conclusions 10 10 10 20 20 develop and improve experimental procedure www.britishcouncil.org 5  Item Index Assessment Assessment Filename Question ID AO1 AO2 AO3 AO4 Page content topic Class 6 Class 6 Science10YP3 Science10YP31b 2 14 Class 6 Class 6 Science10AP5 Science10AP51ci 2 18 Class 6 Class 6 Science10YP3 Science10YP31a 4 14 Class 6 Class 6 Science10AP5 Science10AP51cii 4 18 Class 6 Class 6 Science10NG3 Science10NG31aiii 1 22 Class 6 Class 6 Science10YP3 Science10YP31c 1 2 14 Class 6 Class 6 Science10TM3 Science10TM31f 2 2 26 Class 6 Class 6 Science10YP4 Science10YP41b 2 31 Class 6 Class 6 Science10YP3 Science10YP31d 3 14 Class 7 Class 7 Science10TM3 Science10TM31a 1 26 Class 7 Class 7 Science10TM3 Science10TM31bi 1 26 Class 7 Class 7 Science10TM3 Science10TM31bii 1 26 Class 7 Class 7 Science10SG4 Science10SG41ci, cii 2 2 37 Class 9 Class 9 Science10MS4 Science10MS41aii 1 39 Class 9 Class 9 Science10RR4 Science10RR41ci 1 42 Class 9 Class 9 Science10MS4 Science10MS41bii 2 39 Class 9 Class 9 Science10RR4 Science10RR41cii 2 42 Class 9 Class 9 Science10MS4 Science10MS41ai 2 1 39 Class 9 Class 9 Science10R3 Science10R31b 2 2 48 Class 9 Class 9 Science10DP6 Science10DP61b 5 48 Class 9 Class 9 Science10GK5 Science10GK51c 2 2 50 Class 9 Class 9 ScienceCKV4 ScienceCKV41c 4 54 10.1.1 Chemical Science10PB1 Science10PB1 1 58 substances 10.1.1 Chemical Science10PB6 Science10PB6 1 59 substances 10.1.1 Chemical Science10GD3 Science10GD31d 1 60 substances 10.1.1 Chemical Science10NG1 Science10NG1 1 64 substances 10.1.1 Chemical Science10NG3 Science10NG31aii 1 22 substances 10.1.1 Chemical Science10R5 Science10R51a 4 65 substances 10.1.1 Chemical Science10R1 Science10R1 1 67 substances 10.1.1 Chemical Science10R5 Science10R51b 1 65 substances www.britishcouncil.org 6 10.1.1 Chemical Science10GD3 Science10GD31ci 2 60 substances 10.1.1 Chemical Science10GD3 Science10GD31bi,bii,biii 3 60 substances 10.1.1 Chemical Science10GD3 Science10GD31cii 3 60 substances 10.1.3 Chemical Science10GD1 Science10GD1 1 68 substances 10.1.4 Chemical Science10NG4 Science10NG41ai-ax 10 69 substances 10.1.5 Chemical Science10SG2 Science10SG2 1 72 substances 10.1.5 Chemical Science10NG4 Science10NG41b 3 69 substances 10.1.5 Chemical Science10GD4 Science10GD41bii 1 74 substances 10.1.5 Chemical Science10SG4 Science10SG41bi,bii,biii 1 2 37 substances 10.1.6 Chemical Science10GD4 Science10GD41cii 1 74 substances 10.1.7 Chemical Science10GD4 Science10GD41di 1 74 substances 10.1.7 Chemical Science10GD4 Science10GD41dii 1 74 substances 10.1.8 Chemical Science10GD4 Science10GD41ci 1 74 substances 10.10.1 Chemical Science10MS3 Science10MS31a 2 76 substances 10.2.1 Chemical Science10NG2 Science10NG2 1 80 substances 10.2.2 Chemical Science10R4 Science10R41b 2 81 substances 10.2.3 Chemical Science10NG3 Science10NG31c 5 22 substances 10.2.4 Chemical Science10NB4 Science10NB41b 1 81 substances 10.2.4 Chemical Science10NB4 Science10NB41ci,cii,ciii 1 1 1 81 substances 10.2.6 Chemical Science10NB3 Science10NB31b 3 89 substances 10.3.1 Chemical Science10R2 Science10R2 1 93 substances 10.3.5 Chemical Science10SG3 Science10SG31bi 1 94 substances 10.3.5 Chemical Science10SG3 Science10SG31bii 1 1 94 substances 10.3.5 Chemical Science10PB4 Science10PB4b 2 2 98 substances 10.3.5 Chemical Science10SG3 Science10SG31a 2 94 substances www.britishcouncil.org 7 10.4.1 Chemical Science10NB3 Science10NB31ai 3 89 substances 10.4.1 Chemical Science10GD3 Science10GD31a 3 60 substances 10.4.2 Chemical Science10R4 Science10R41a 4 81 substances 10.5.1 Chemical Science10PB4 Science10PB4aii 2 98 substances 10.5.1 Chemical Science10PB4 Science10PB4ai 1 4 98 substances 10.6.1 Chemical Science10PB3 Science10PB31aii 1 101 substances 10.6.1 Chemical Science10PB3 Science10PB31ai 1 1 101 substances 10.6.1 Chemical Science10R3 Science10R31a 2 48 substances 10.6.1 Chemical Science10NG3 Science10NG31ai 2 22 substances 10.6.1 Chemical Science10NG3 Science10NG31b 2 22 substances 10.6.2 Chemical Science10PB3 Science10PB31ci 1 101 substances 10.6.2 Chemical Science10PB3 Science10PB31cii 1 101 substances 10.6.2 Chemical Science10SG5 Science10SG51aii 1 103 substances 10.6.2 Chemical Science10SG5 Science10SG51b 1 103 substances 10.6.2 Chemical Science10SG5 Science10SG51ai 3 103 substances 10.6.2 Chemical Science10PB3 Science10PB31ciii 1 101 substances 10.6.3 Chemical Science10GD4 Science10GD41a 2 74 substances 10.6.3 Chemical Science10NB1 Science10NB1 1 108 substances 10.6.3 Chemical Science10SG1 Science10SG1 1 109 substances 10.8.2 Chemical Science10SG3 Science10SG31c 4 94 substances 10.8.5 Chemical Science10PB3 Science10PB31bi 1 101 substances 10.8.5 Chemical Science10PB3 Science10PB31bii 1 101 substances 10.8.5 Chemical Science10PB3 Science10PB31di 1 101 substances 10.8.5 Chemical Science10PB3 Science10PB31dii 1 1 101 substances 10.8.5 Chemical Science10PB3 Science10PB31diii 1 1 101 substances www.britishcouncil.org 8 10.8.6 Chemical Science10NB3 Science10NB31c 4 89 substances 10.8.7 Chemical Science10NB3 Science10NB31aii 1 89 substances 10.8.7 Chemical Science10SG4 Science10SG41a 2 37 substances 10.9.1 Chemical Science10CKV3 Science10CKV31a 1 109 substances 10.9.1 Chemical Science10GD4 Science10GD41bi 1 74 substances 10.9.2 Chemical Science10NB4 Science10NB41a 1 81 substances 10.1.19 Effects of Science10SK4 Science10SK4 2 113 current 10.1.21 Effects of Science10RR1 Science10RR1 1 115 current 10.1.21 Effects of Science10NB2 Science10NB2 1 116 current 10.1.21 Effects of Science10AP2 Science10AP2 1 118 current 10.1.21 Effects of Science10MS4 Science10MS41bi 2 2 39 current 10.12.4 Effects of Science10RR3 Science10RR31b 2 119 current 10.2.15 Effects of Science10SD1(1) Science10SD1di 1 2 123 current 10.2.15 Effects of Science10SD1(1) Science10SD1di 1 2 123 current 10.2.15 Effects of Science10SD1(1) Science10SD1dii 2 123 current 10.2.15 Effects of Science10SD1(1) Science10SD1dii 2 123 current 10.2.15 Effects of Science10ST4 Science10ST41ai 4 126 current 10.2.16 Effects of Science10SD1(1) Science10SD1c 1 2 123 current 10.2.16 Effects of Science10SD1(1) Science10SD1c 1 2 123 current 10.2.16 Effects of Science10ST4 Science10ST41b 2 2 126 current 10.2.16 Effects of Science10SD1(1) Science10SD1a 1 123 current 10.2.16 Effects of Science10SD1(1) Science10SD1b 1 123 current 10.2.16 Effects of Science10SD1(1) Science10SD1a 1 123 current 10.2.16 Effects of Science10SD1(1) Science10SD1b 1 123 current 10.3.22 Effects of Science10TM2 Science10TM2 1 132 current www.britishcouncil.org 9 10.3.22 Effects of Science10RR3 Science10RR31c 2 2 119 current 10.3.23 Effects of Science10RR3 Science10RR31a 2 119 current 10.3.23 Effects of Science10SK3 Science10SK3 2 134 current 10.3.23 Effects of Science10ST4 Science10ST41c 2 126 current 10.3.24 Effects of Science10SK6 Science10SK61b 3 135 current 10.3.24 Effects of Science10RR3 Science10RR31d 1 2 119 current 10.3.24 Effects of Science10RR3 Science10RR31e 4 119 current 10.3.27 Effects of Science10GK3 Science10GK31b 4 138 current 10.3.28 Effects of Science10YP2 Science10YP2 1 141 current 10.3.29 Effects of Science10GK3 Science10GK31a 2 138 current 10.3.30 Effects of Science10TM3 Science10TM31d 1 26 current 10.3.30 Effects of Science10TM3 Science10TM31c 2 2 26 current 10.3.31 Effects of Science10TM3 Science10TM31e 2 26 current 10.4.8 Effects of Science10SK6 Science10SK61ai 1 2 135 current 10.4.8 Effects of Science10ST4 Science10ST41aii 1 2 126 current 10.4.9 Effects of Science10SK6 Science10SK61aii 1 2 135 current 10.7.4 Effects of Science10GK1 Science10GK1 1 143 current 10.8.19 Effects of Science10RR4 Science10RR41a 5 42 current 10.8.22 Effects of Science10GK3 Science10GK31cii 2 138 current 10.1.12 Living world Science10MS1 Science10MS1 1 144 10.10.2 Living world Science10DP6 Science10DP61a 3 48 10.10.2 Living world Science10CKV5 Science10CKV51ii 2 145 10.10.2 Living world Science10CKV5 Science10CKV51ai 4 145 10.11.4 Living world Science10AP5 Science10AP51b 2 18 10.12.3 Living world Science10DP3 Science10DP31c 1 148 10.2.10 Living world Science10CKV1 Science10CKV1 1 150 10.3.10 Living world Science10DP4 Science10DP41a 1 151 10.3.10 Living world Science10DP4 Science10DP41bi 1 151 10.3.10 Living world Science10DP4 Science10DP41bii 1 151 10.3.10 Living world Science10DP4 Science10DP41ci 1 151 www.britishcouncil.org 10 10.3.10 Living world Science10DP4 Science10DP41cii 1 151 10.3.10 Living world Science10CKV2 Science10CKV2 1 154 10.3.10 Living world Science10DP4 Science10DP41d 1 3 151 10.3.11 Living world Science10AP1 Science10AP1 1 155 10.3.11 Living world Science10CKV3 Science10CKV31c 3 109 10.3.14 Living world Science10DP3 Science10DP31a 2 1 148 10.3.16 Living world Science10DP3 Science10DP31b 3 148 10.3.17 Living world Science10CKV5 Science10CKV51c 3 145 10.3.9 Living world Science10AP3 Science10AP31bii 2 157 10.3.9 Living world Science10CKV3 Science10CKV31b 2 109 10.3.9 Living world Science10AP3 Science10AP31a 3 157 10.3.9 Living world Science10AP3 Science10AP31ci 3 157 10.3.9 Living world Science10AP3 Science10AP31cii 4 157 10.3.9 Living world Science10MS5 Science10MS51b 5 161 10.3.9 Living world Science10AP3 Science10AP31bi 1 157 10.4.3 Living world Science10AP4 Science10AP41a 2 163 10.4.3 Living world Science10MS3 Science10MS31dii 3 76 10.5.6 Living world Science10AP5 Science10AP51ai-v 6 18 10.5.6 Living world Science10CKV3 Science10CKV31d 2 2 109 10.5.9 Living world Science10CKV5 Science10CKV51b 3 145 10.6.4 Living world Science10MS3 Science10MS31b 1 76 10.6.4 Living world Science10MS3 Science10MS31ci 1 76 10.8.12 Living world Science10MS2 Science10MS2 1 165 10.8.8 Living world Science10AP3 Science10AP31d 4 157 10.9.4 Living world Science10DP2 Science10DP2 1 166 10.9.5 Living world Science10AP4 Science10AP41b 1 2 163 10.1.14 Natural Science10GK4 Science10GK41ai 1 167 phenomena 10.1.14 Natural Science10TM4 Science10TM41bii 2 170 phenomena 10.1.15 Natural Science10GK2 Science10GK2 1 174 phenomena 10.1.15 Natural Science10GK4 Science10GK41b 2 1 167 phenomena 10.1.16 Natural Science10SK5 Science10SK5c 1 175 phenomena 10.1.17 Natural Science10GK4 Science10GK41aii 2 167 phenomena 10.2.14 Natural Science10RR2 Science10RR2 1 179 phenomena 10.2.14 Natural Science10SK5 Science10SK5d 5 175 phenomena 10.3.18 Natural Science10SK1 Science10SK1b 2 181 phenomena www.britishcouncil.org 11 10.3.18 Natural Science10SK1 Science10SK1a 3 181 phenomena 10.3.19 Natural Science10ST3 Science10ST31aii 2 183 phenomena 10.3.19 Natural Science10GK4 Science10GK41aiii 1 167 phenomena 10.3.21 Natural Science10TM4 Science10TM41bi 1 170 phenomena 10.4.6 Natural Science10YP4 Science10YP41aii 1 31 phenomena 10.4.6 Natural Science10YP4 Science10YP41aiv 1 31 phenomena 10.4.6 Natural Science10RR5 Science10RR51ci 3 186 phenomena 10.4.6 Natural Science10YP4 Science10YP41aiii 3 31 phenomena 10.4.6 Natural Science10RR5 Science10RR51cii 3 186 phenomena 10.4.7 Natural Science10TM4 Science10TM41ai 2 170 phenomena 10.4.7 Natural Science10RR5 Science10RR51b 1 186 phenomena 10.4.7 Natural Science10YP4 Science10YP41ai 1 31 phenomena 10.4.7 Natural Science10ST3 Science10ST31b 2 183 phenomena 10.4.7 Natural Science10TM4 Science10TM41aii 2 170 phenomena 10.5.12 Natural Science10ST3 Science10ST31ai 1 2 183 phenomena 10.7.2 Natural Science10SK5 Science10SK5a 2 175 phenomena 10.7.2 Natural Science10SK5 Science10SK5b 2 175 phenomena 10.8.13 Natural Science10ST1 Science10ST1 1 192 phenomena 10.8.14 Natural Science10RR5 Science10RR51d 4 186 phenomena 10.8.14 Natural Science10YP4 Science10YP41c 1 2 1 31 phenomena 10.8.15 Natural Science10GK4 Science10GK41c 2 167 phenomena 10.8.15 Natural Science10RR5 Science10RR51a 2 186 phenomena 10.8.17 Natural Science10TM4 Science10TM41c 1 2 170 phenomena 10.1.21 Natural Science10GK3 Science10GK31ci 2 138 resources 10.1.22 Natural Science10MS5 Science10MS51a 1 161 resources www.britishcouncil.org 12 10.1.22 Natural Science10GK5 Science10GK51ai aii aiii 3 50 resources 10.1.22 Natural Science10GK5 Science10GK51b 2 50 resources 10.1.23 Natural Science10GD4 Science10GD41e 2 2 74 resources 10.3.32 Natural Science10PB2 Science10PB2 1 193 resources 10.3.32 Natural Science10SG5 Science10SG51c 3 1 103 resources 10.3.32 Natural Science10NB4 Science10NB41d 2 2 81 resources 10.5.19 Natural ScienceCKV4 ScienceCKV41b 1 54 resources 10.5.19 Natural SCIENCE10DP1 Science10DP1 1 194 resources 10.5.19 Natural ScienceCKV4 ScienceCKV41a 2 54 resources 10.5.20 Natural Science10AP6 Science10AP61a 4 195 resources 10.6.9 Natural Science10DP5 Science10DP51a 1 198 resources 10.6.9 Natural Science10YP1 Science10YP1 1 200 resources 10.6.9 Natural Science10ST2 Science10ST2 1 202 resources 10.6.9 Natural Science10ST5 Science10ST51a 1 203 resources 10.6.9 Natural Science10PB5 Science10PB51a 2 205 resources 10.6.9 Natural Science10PB5 Science10PB51bi 2 205 resources 10.6.9 Natural Science10AP6 Science10AP61c 2 195 resources 10.6.9 Natural Science10PB5 Science10PB51bii 3 205 resources 10.6.9 Natural Science10SK6 Science10SK61c 4 135 resources 10.6.9 Natural Science10MS4 Science10MS41c 4 39 resources 10.8.24 Natural Science10AP6 Science10AP61b 2 195 resources 10.8.27 Natural Science10ST5 Science10ST51b 4 203 resources 10.8.27 Natural Science10RR4 Science10RR41b 3 42 resources 10.8.27 Natural Science10DP5 Science10DP51b 2 2 198 resources Science10YP3 www.britishcouncil.org 13 Item identity AO1 AO2 AO3 AO4 Content Reference(s) Marks marks marks marks marks Science10YP3 4 10.3.25 Explain how an electric 4 current flowing through a wire 1a heats the wire Science10YP3 2 10.3.24 Explain the impact of 2 resistors in series and in parallel 1b on the resistance of a simple circuit. Science10YP3 1 2 No syllabus reference for paying 3 for kWh – see Chapter 12 p219 1c and p220 of NCERT textbook X Science10YP3 3 10.8.23 Explain the greenhouse 3 effect and how human activities 1d contribute to global warming through burning fossil fuels, agriculture and industry linked to the greenhouse effect of different atmospheric gases-methane and carbon dioxide. Total marks 10 2 12 Item purpose The question assesses the understanding of students regarding Joule’s heating effect, the advantages of parallel connection in home appliances, comparison of the cost of the energy to operate electrical household appliances, the greenhouse gas used in refrigerators and its impact to the environment. Questions www.britishcouncil.org 14 1 Fig. 1 shows the filament in a lamp. Fig. 1 The filament is made from a very thin piece of metal. When there is a current in the filament it glows brightly and becomes very hot. 1 (a) Explain how the current causes the filament to become hot. (4 marks) 1 (b) Lamps in the home are connected in parallel. Give two reasons why lamps are connected in parallel. (2 marks) 1 (c) The cost of electricity is Rs 4 per kilowatt-hour. Calculate the cost of using a 100 W lamp for 8 hours. (3 marks) 1 (d) The coolant in a modern refrigerator is called HFC. HFC does not damage the ozone layer. However, HFC is a powerful greenhouse gas. Explain why HFC must not be released into the atmosphere. (3 marks) (Total marks 12) Mark scheme www.britishcouncil.org 15  1. 1 (a) Explain how the current causes the filament to become hot. Answer Guidance the filament/metal has resistance; ALLOW higher level explanations i.e. Any four from: work is done by the resistance work done against the current; of the circuit against the electrons releasing heat energy; when they collide with the ions of the electrical energy is transferred to metal lattice thermal/heat energy; 1 (b) Lamps in the home are connected in parallel. Give two reasons why lamps are connected in parallel. Answer Guidance Any two from: each lamp gets the full supply voltage; if one lamp breaks the others remain working; they can be switched on and off independently; 1 (c) The cost of electricity is Rs 4 per kilowatt-hour. Calculate the cost of using a 100 W lamp for 8 hours. Answer Guidance If answer = Rs 3.2 award 3 marks conversion: 100 W = 0.1 kW; Substitution : 0.1 x 4 x 8; Calculation: Rs 3.2; 1 (d) The coolant in a modern refrigerator is called HFC. HFC does not damage the ozone layer. However, HFC is a powerful greenhouse gas. Explain why HFC must not be released into the atmosphere. www.britishcouncil.org 16  Answer Guidance Idea that thermal radiation absorbed and ALLOW they absorb the Sun’s radiation re-emitted by the Earth is absorbed by gases / CO2 / methane / HFC (in the atmosphere); increased greenhouse effect / global warming/heating; climate change; named consequence of climate change e.g., drought / sea level rise / melting icecaps; Science10AP5 www.britishcouncil.org 17  Item identity AO1 AO2 AO3 AO4 Content Reference(s) Marks marks marks marks marks Science10AP51ai- 6 10.5.6 Draw and label 6 v diagrams showing the flow of nutrients in plants and animals. 7.1.5 Identify examples of plant and animal organs and organ systems Science10AP51b 2 10.11.4 Understands the 2 need for balanced nutrition and potential impact if it is not achieved. 6.1.6 Classify foods as sources of particular nutritional requirements: Rice and other grains and sugars for carbohydrates Pulses, eggs and meat for proteins Oils and fats and dairy products for lipids Various drinks for water Fruits and vegetables or vitamins and minerals Vegetables for fibre Science10AP51ci 2 6.1.6 Classify foods as 2 sources of particular Science10AP51cii 4 4 nutritional requirements: Rice and other grains and sugars for carbohydrates Pulses, eggs and meat for proteins www.britishcouncil.org 18  Oils and fats and dairy products for lipids Various drinks for water Fruits and vegetables or vitamins and minerals Vegetables for fibre Total marks 14 Item purpose The question assesses the skill to draw and present information and understands the need for balanced nutrition and potential impact if it is not achieved. Question(s) 1 A diagram of the digestive system is shown. 1(a) Identify the letters on the diagram where: www.britishcouncil.org 19 1(a)(i) starch is digested __________ and __________ (2 marks) 1(a)(ii) saliva is produced __________ (1 mark) 1(a)(iii) the environment is acidic __________ (1 mark) 1(a)(iv) water is re-absorbed __________ (1 mark) 1(a)(v) egestion occurs __________ (1 mark) 1(b) State the name of organ: E J (2 marks) 1(c) One requirement of a balanced diet is fibre. Fibre cannot be digested or absorbed. 1(c)(i) State one source of fibre and explain why it is necessary in a (2 marks) balanced diet. 1(c)(ii) State four other requirements of a balanced diet. (4 marks) (Total marks 14) Mark scheme 1 (a) Identify the letters on the diagram where: starch is digested __________ and __________ saliva is produced __________ the environment is acidic __________ www.britishcouncil.org 20  water is re-absorbed __________ egestion occurs __________ Answer Guidance (a)(i) A; H; (a)(ii) A (a)(iii) D; (a)(iv) F; (a)(v) G 1 (b) State the name of organ: E J Answer Guidance E – pancreas; J – liver; 1 (c)(i) State one source of fibre and explain why it is necessary in a balanced diet. Answer Guidance Plants / vegetables / fruit / named ALLOW lowers risk of cancer/heart disease vegetable/fruit; Helps to move food through (the alimentary canal) / prevents constipation 1 (c)(ii) State four other requirements of a balanced diet. Answer Guidance Any four from: Vitamins Minerals / named mineral e.g., iron Protein Fat Carbohydrate Water www.britishcouncil.org 21 Science10NG3 Item identity AO1 AO2 AO3 AO4 Content Reference(s) Marks marks marks marks marks Science10NG31ai 2 10.6.1 Write balanced 2 word and symbol equations, Science10NG31aii 1 10.1.1 Define types of 1 chemical reactions: combination, decomposition, displacement, double displacement, precipitation, neutralization, oxidation and reduction. Science10NG31aiii 1 LO: applies scientific 1 concepts in daily life and solving problems, such as, suggest precautions Science10NG31b 2 10.6.1 Write balanced 2 word and symbol equations, Science10NG31c 5 10.2.3 5 Describe how to perform the following practical activities … (ii) Action of heat on ferrous sulphate crystals Total marks 1 10 11 Item purpose The question assesses the understanding and ability of students to interpret chemical reactions and relate their impact on the environment. www.britishcouncil.org 22 Question(s) 1 Calcium oxide reacts vigorously with water. 1(a)(i) Construct the balanced symbol equation for the reaction between (2 marks) calcium oxide and water. 1(a)(ii) State and explain the type of reaction between calcium oxide and (1 mark) water. 1(a)(iii) State two precautions you should take when reacting calcium oxide (1 mark) with water. 1(b) The product of the reaction in (a)(i) can be used to make calcium carbonate (CaCO3). Identify: the reacting gas the other product formed (2 marks) 1(c) Describe how to obtain a dry sample of iron oxide from a solution of ferrous sulfate. You should give experimental details, observations, and precautions at each stage of the procedure. (5 marks) (Total 11 marks) www.britishcouncil.org 23 Mark scheme 1 (a)(i) Construct the balanced symbol equation for the reaction between calcium oxide and water. Answer Guidance Left hand side correct; Right hand side correct; Ca + H2O Ca(OH)2 1 (a)(ii) State and explain the type of reaction between calcium oxide and water. Answer Guidance Combination; Dependent mark (because) more than one reactant, only one product; OR Exothermic; (because) heat released. 1 (a)(iii) State two precautions you should take when reacting calcium oxide with water. Answer Guidance Any two from: Wear goggles; Use a heat resistant container; Use small quantities of CaO. 1 (b) The product of the reaction in (a)(i) can be used to make calcium carbonate (CaCO3). Identify: the reacting gas the other product formed Answer Guidance Carbon dioxide / CO2; Water / H2O 1 (c) Describe how to obtain a dry sample of iron oxide from a solution of ferrous sulfate. You should give experimental details, observations and precautions at each stage of the procedure. www.britishcouncil.org 24 Answer Guidance Indicative science Points must be awarded from both methods and precautions – max 3 marks if not Methods / observation Heat solution to evaporate water. Crystals of ferrous sulfate form Heat ferrous sulfate in a test tube Sulfur oxides are given off Decolorizes as iron oxide forms Precautions: Sulfur oxides are toxic – don't inhale deeply Wear goggles Ventilated room Hold the test tube using tongs Level of response Level Description Marks 4 Clear well-structured explanation linking effects to causes or 4 underpinning theory. 3 Clear description of relevant facts with some explanation relating 3 effects to causes or underpinning theory. 2 Description of the basic facts but no link of effects to causes or 2 underpinning theory. 1 Limited isolated descriptive points relevant to the topic 1 0 Nothing worthy of credit 0 www.britishcouncil.org 25 Science10TM3 Item identity AO1 AO2 AO3 AO4 Content Reference(s) Marks marks marks marks marks Science10TM31a 1 1 Science10TM31bi 1 1 7.2.7 Describe the Science10TM31bii 1 outcome of 1 investigations of electromagnetism in terms of the magnetic fields that form around current-carrying wires and solenoids. Science10TM31c 2 2 4 Science10TM31d 1 10.3.30 Explain how 1 the movement of a magnet in a coil of wire generates a current and Flemming’s right hand rule is used to determine the direction of the current. Science10TM31e 2 10.3.31 Explain how 2 AC current is produced (in a generator). Science10TM31f 2 2 4 Total marks 8 6 14 Item purpose The question assesses the understanding of magnetic field due to various current carrying conductors and the factors on which the intensity of this magnetic field depends, and also child can learn how to produce electricity from magnetism. www.britishcouncil.org 26 Question(s) 1 1 (a) Which diagram, A, B or C shows the shape of the magnetic field around a current-carrying conductor? (1 marks) 1 (b) An electrical current is in the direction P to Q as shown in the diagram. The magnetic field strength is measured at R and S. (i) State and explain where the field strength is largest. (1 mark) (ii) The current in the wire is reversed. Explain how this affects the magnetic field at R. (1 mark) 1 (c) Two solenoids are coiled around a non-conducting rod as shown in the diagram. www.britishcouncil.org 27  The switch is closed. Explain why the reading on the voltmeter first increases and then returns to zero. (4 marks) 1 (d) When there is a reading on the voltmeter there is also a current in the coil. State the name of the rule used to determine the direction of this current. (1 marks) 1 (e) State and explain the type of current produced in a generator. (2 marks) 1 (f) In mountainous areas dams are constructed. Water held behind the dam is released through a generator to produce electricity. Explain why some people are opposed to the construction of dams. (4 marks) (Total marks 14) www.britishcouncil.org 28 Mark scheme 1. 1 (a) Which diagram, A, B or C shows the shape of the magnetic field around a current-carrying conductor? Answer Guidance (a) A; 1 (b) (i) State and explain where the field strength is largest. 1 (b) (ii) The current in the wire is reversed. Explain how this affects the magnetic field at R. Answer Guidance (b)(i) R because field lines are closer IGNORE R because it is closer to the wire together/more dense / more flux density; ALLOW higher flux density at R (b)(ii) same strength opposite direction; 1 (c) Explain why the reading on the voltmeter first increases and then returns to zero. Answer Guidance voltage / emf is induced; magnetic field; changing magnetic field; returns to zero when magnetic field is constant / stops changing; 1 (d) When there is a reading on the voltmeter there is also a current in the coil. State the name of the rule used to determine the direction of this current. Answer Guidance Fleming’s right hand (grip) rule; 1 (e) State and explain the type of current produced in a generator. Answer Guidance alternating; a coil/solenoid rotates in a magnetic field; www.britishcouncil.org 29  1 (f) Explain why some people are opposed to the construction of dams. Answer Guidance indicative science: loss of habitat loss of water for irrigation downstream loss of farmland very expensive to build can become silted up / need dredging possible to generate electricity more cheaply by other means climate change may result in insufficient rainfall to fill the dam. www.britishcouncil.org 30 Science10YP4 Item identity AO1 AO2 AO3 AO4 Content Reference(s) Marks marks marks marks marks Science10YP4 1 10.4.7 Calculate the magnification 1 and power of a convex spherical 1ai lens Science10YP4 1 10.4.6 Using the lens formula 1 calculate object distance, image 1aii distance and focal length of a convex spherical lens Science10YP4 3 10.4.6 3 1aiii Science10YP4 1 10.4.6 1 1aiv Science10YP4 2 Learning Outcome calculates 2 using the data given, such as, 1b …...... power of a lens, electric power, etc. & NCERT textbook X Ch 10 page 184 Science10YP4 1 2 1 10.8.14 Explain how sight defects 4 can occur (long and short 1c sightedness) and how they can be corrected. Total marks 1 10 1 12 Item purpose The question assesses the understanding of students regarding calculation of the object distance, the image distance of a convex lens, the power and focal length of a combination of two convex lens, long-sightedness and its correction. Questions 1 Fig. 1 shows the image formed by a lens when it is used as a magnifying glass. www.britishcouncil.org 31  Fig. 1 The height of the image hi is four times larger than the height of the object ho. 1 (a) (i) State the magnification M of the image. (1 mark) (ii) Use your value of M to determine the ratio of the image distance v to the object distance u. v = ….................... (1 mark) (iii) The focal length f of the lens is 20 cm. Using your answer in (a)(ii) in the lens equation: calculate the object distance u. (3 marks) (iv) Using your answer in (a)(ii) and (a)(iii) calculate v. (1 mark) 1 (b) The power P of a lens is calculated using the equation: www.britishcouncil.org 32  Calculate the power of lens with a focal length f = 20 cm. State the unit. (2 marks) 1 (c) Fig. 2 shows the effect of long sightedness in an eye. Fig. 2 Explain what causes long-sightedness and what can be done to correct it. (4 marks) Mark scheme 1 (a) (i) State the magnification M of the image. (1 mark) (ii) Use your value of M to deduce the ratio of the image distance v to the object distance u. (1 mark) (iii) The focal length f of the lens is 20 cm. Using your answer in (a)(ii) in the lens equation: calculate the object distance u. Answer Guidance (i) M = 4 (ii) v = 4U or v/u = 4; www.britishcouncil.org 33  (iii) If answer u = -15 cm award 3 marks ALLOW 15 Substitution: ; Rearrangement to give u = ¾ x 20; Calculation u = -15 cm; (iv) (4 x –15 =) -60 cm; ALLOW ecf (a)(ii) x (a)(iii) 1 (b) Calculate the power of lens with a focal length f = 20 cm. State the unit. Answer Guidance If answer P = 5 D award 2 marks ALLOW 0.05 D = 1 mark Conversion 20 cm = 0.2; Substitution, calculation and unit D/Dioptre; 1 (c) Explain what causes long-sightedness and what can be done to correct it. Answer Guidance Indicative science ALLOW lens changes shape Causes: ALLOW lens changes position Increased curvature of lens; ALLOW eyeball changes shape Dislocation of lens; ALLOW image is not in focus Shortening of eyeball; ALLOW only distant images are focused on Image is formed behind retina the retina (when observing a near point N’) Corrections: Spectacles / contact lenses Convex lens Surgery www.britishcouncil.org 34  Science10SG4 Item identity AO1 AO2 AO3 AO4 Content Reference(s) Marks marks marks marks marks SCIENCE10SG41a 2 10.8.7 Describe the 2 properties and uses of ethanol and ethanoic acid. SCIENCE10SG41bi, 1 2 10.1.5 Define bonding 3 bii, biii as ionic, covalent, and metallic and relate this to physical and chemical properties. 10.8.7 Describe the properties and uses of ethanol and ethanoic acid. SCIENCE10SG41ci, 2 2 7.2.2 Explain that 4 cii chemical reactions form new products. Total marks 3 4 2 9 Item purpose The question assesses the students understanding of the physical and chemical properties of important organic compounds such as ethanol. Question(s) 1 Ethanol is an important carbon compound. 1(a) State one property and one use of ethanol. (2 marks) www.britishcouncil.org 35 1(b) Ethanol has the chemical formula C2H5OH. Ethanol can be converted to ethene C2H4. 1(b)(i) Determine the number of covalent bonds in one molecule of ethanol. (1 mark) 1(b)(ii) Name the acid that is used to convert ethanol to ethene. (1 mark) 1(b)(iii) Suggest why the acid that is used to convert ethanol to ethene is (1 mark) described as a dehydrating agent. 1(c) In an investigation, a piece of sodium metal is added to excess ethanol. The gas produced in the reaction is collected as shown in Fig. 1. Fig. 1 The volume of gas collected is recorded every 10 seconds as shown in Table 1. Results Time (seconds) Volume of gas (cm3) 0 0 10 20 20 40 30 58 www.britishcouncil.org 36  40 72 50 80 60 80 Table 1 1(c)(i) Describe how the reaction changed during the reaction. Suggest why the (3 marks) reaction changed in this way 1(c)(ii) Deduce the identity of the gas released in this reaction. (1 mark) (Total marks 9) Mark scheme 1 (a) State one property and one use of ethanol. Answer Guidance Property: colourless / liquid at room temp. / flammable / soluble in water ; Use: medicine / anti-freeze / solvent / fuel ; 1 (b)(i) Determine the number of covalent bonds in one molecule of ethanol. Answer Guidance 8; 1 (b)(ii) Name the acid that is used to convert ethanol to ethene. Answer Guidance sulfuric acid / H2SO4 ; 1 (b)(iii) Suggest why the acid that is used to convert ethanol to ethene is described as a dehydrating agent. Answer Guidance It removes H2O / water (from ethanol); 1 (c)(i) Describe how the reaction changed during the reaction. Suggest why the reaction changed in this way Answer Guidance It slows down; www.britishcouncil.org 37 (then) stops; sodium is used up; 1 (c)(ii) Deduce the identity of the gas released in this reaction. Answer Guidance Hydrogen / H2 ALLOW H www.britishcouncil.org 38 Science10MS4 Item identity AO1 AO2 AO3 AO4 Content Reference(s) Marks marks marks marks marks Science10MS41ai 2 1 3 9.4.25 Explain how the addition of fertilisers Science10MS41aii 1 1 (natural manure and man- made ammonium nitrate) change crop productivity but can have negative effects. Science10MS41bi 10.1.21 Define an 4 ecosystem in terms of 2 2 communities of organisms interacting with abiotic factors Science10MS41bii 2 9.9.7 Explain the impact 2 of industry and agriculture on …...fertiliser run off promoting eutrophication of water courses Science10MS41c 4 10.6.9 Explain how 4 different forms of energy are created and used- fossil fuels, nuclear, solar, biogas, ethanol wood/biomass, wind, water and tidal and describe the advantages and disadvantages of each Total marks 7 7 14 www.britishcouncil.org 39 Item purpose The question assesses the students' understanding about the ecosystems made by man. It also tests their understanding about the comparative analysis of different types of fuels. Question(s) 1 Animal dung is used as an organic fertiliser. 1 (a)(i) Explain what is meant by the term organic fertiliser. (3 marks) 1 (a)(ii) Name one man-made fertiliser. (1 marks) 1 (b)(i) In periods of high rainfall, fertiliser can flow into lake ecosystems. Explain what is meant by the term ecosystem. (4 marks) 1 (b)(ii) Suggest two negative impacts of fertiliser in lake ecosystems. (2 marks) 1 (c) Animal dung can be used as a fuel and burned to heat homes. Animal dung can also be fermented to produce biogas. Biogas can be burned to heat homes. Explain the advantages of using animal dung to produce biogas. (4 marks) (Total marks 14) www.britishcouncil.org 40 Mark scheme 1 (a)(i) Explain what is meant by the term organic fertiliser. Answer Guidance Produced by a plant/animal; To increase / replenish nutrients in soil; For the production of crops 1 (a)(ii) Name one man-made fertiliser. Answer Guidance Ammonium nitrate /AVP; 1 (b)(i) Explain what is meant by the term ecosystem. Answer Guidance Organisms/plants animals; In a habitat / community; Interact with each other/biotic; ALLOW named abiotic factor e.g., climate Interact with the surroundings/abiotic; 1 (b)(ii) Suggest two negative impacts of fertiliser in lake ecosystems. Answer Guidance increased growth of plants / algae; ALLOW a description of eutrophication i.e., Eutrophication; Deoxygenation of water by (respiration) of decomposers feeding on decaying algae. 1 (c) Explain the advantages of using animal dung to produce biogas. Answer Guidance Indicative science: clean / no smoke / no ash; Smoke from burning dung affects lungs; (biogas) releases more heat when it burns; The dung can still be used as a fertiliser; Can be used in other processes e.g. electrical generators; www.britishcouncil.org 41 Science10RR4 Item identity AO1 AO2 AO3 AO4 Content Reference(s) Marks marks marks marks marks Science10RR41a 5 10.8.19 Explain how a 5 generator is used to produce electricity... Science10RR41b 3 10.8.27 Explain the 3 advantages and disadvantages of large dam projects. Science10RR41ci 1 1 9.1.12 Classify resources as renewable and non- Science10RR41cii 2 2 renewable. Total marks 8 3 11 Item purpose The question assesses the learner’s ability to understand the impact of dam construction on the environment and the importance of renewable energy. Source(s) www.britishcouncil.org 42 Source information : google images https://www.google.com/search?q=tehri%20dam%20images&tbm=isch&hl=en&rlz=1C1JZAP_e nIN932IN932&sa=X&ved=0CB4QtI8BKABqFwoTCODqs_- 47O8CFQAAAAAdAAAAABAW&biw=1519&bih=666 Question(s) 1. 1Large dams are used to generate electricity. 1 (a) Use words from the list to complete the sentences about electricity generation. You may use each word once, more than once or not at all. attract chemical electrical generator kinetic motor potential repel rotate Water behind the dam has __________ energy. This energy is transferred to __________ energy when the water flows through a turbine. The turbine turns a __________. This causes a large magnet to __________ inside a coil of wire and produce __________ energy. (5 marks) 1 (b) Describe three environmental impacts of large dams. (3 marks) www.britishcouncil.org 43 1 (c) (i) Dams are a renewable source of energy. Explain what is meant by a renewable source of energy. (1 marks) 1 (c) (ii) Give two more examples of renewable sources of energy. (2 marks) (Total marks 11) www.britishcouncil.org 44 Mark scheme 1 (a) Use words from the list to complete the sentences about electricity generation. Answer Guidance Potential; Kinetic; Generator; Rotate; Electrical; 1 (b) Describe three environmental impacts of large dams. Answer Guidance Any three from: IGNORE cost / impacts on people Loss of habitat / deforestation; Loss of farmland; Silting up; Loss of water for downstream irrigation; Loss of nutrients in silt for downstream agriculture; AVP; 1 (c) (i) Dams are a renewable source of energy. Explain what is meant by a renewable source of energy. 1 (c) (ii) Give two more examples of renewable sources of energy. Answer Guidance (i) always available / not finite / won’t run out; (ii) Any two from Solar; Wind; Wave; Tidal; Geothermal. www.britishcouncil.org 45 Science10R3 Item identity AO1 AO2 AO3 AO4 Content Reference(s) Marks marks marks marks marks Science10R31a 2 10.6.1 Write balanced word 2 and symbol equations, including phase information for common examples of combination, decomposition, displacement, double displacement, precipitation, neutralization, oxidation and reduction reactions. Science10R31b 2 2 9.2.5 Explain how to design 4 and conduct an experiment to verify the law of conservation of mass in a chemical reaction. Total marks 2 4 6 Item purpose The question assesses …students' ability to write a balanced chemical equation. Identify the principal on which balancing is done. Question(s) 1. The reaction of lead nitrate with potassium iodide produces lead iodide and potassium nitrate. (a) Construct a balanced chemical equation for this reaction. (2 marks) (b) Explain why chemical reactions are balanced. (4 marks) www.britishcouncil.org 46 Mark scheme 1 (a) Construct a balanced chemical equation for this reaction. Answer Guidance all formulae correct; PbNO3 + KI → PbI2 + KNO3 = 1 mark balancing; Pb (NO3)2 + 2KI → PbI2 + 2KNO3; Dependent mark – only award if the formulae mark is awarded 1 (b) Explain why chemical reactions are balanced. Answer Guidance Technique described, ALLOW e.g., heat known mass of Mg ribbon e.g., oxidation ; until fully oxidised ALLOW use mass of oxidised Mg in MgO Chemical formula of product to deduce amount of oxygen added; mass of products = mass of reactants; (because) mass is conserved. www.britishcouncil.org 47 Science10DP6 Item identity AO1 AO2 AO3 AO4 Content Reference(s) Marks marks marks marks marks SCIENCE10DP61a 3 10.10.2 Mendel’s work on 3 heredity in plants SCIENCE10DP61b 5 9.3.11 Explain how 5 selective breeding in plants and animals is used to improve quality, yield and manage diseases. Total marks 3 5 8 Item purpose The question assesses the students’ understanding of Mendel’s work, ability to analyse scientific information, interpret patterns and relationships. Question(s) 1 Gregor Mendel studied pea plants. This helped him to understand how features are passed from parents to offspring. 1 (a) Suggest three reasons why Mendel studied pea plants. (3 marks) 1 (b) Mendel’s pea plants flowered with a range of colours. He could not predict which seeds would produce which colour of flower. (5 marks) (Total marks 8) www.britishcouncil.org 48 Mark scheme 1 (a) Suggest three reasons why Mendel studied pea plants. Answer Guidance Any three from: Easy to grow; ALLOW quick to mature Have observable features/characteristics; Reproduce rapidly; Easy to pollinate; Can grow successive generations in a short time/season; 1 (b) Use ideas about selective breeding to explain how Mendel was able to ensure that his seeds would only produce white flowers. Answer Guidance Any five from: Choose the plants with white flowers; Breed them together; Select the offspring with white flowers; Breed them together; Repeat for a few more generations; Detail – e.g., transfer the pollen manually/use a pollen brush / cover the white flowers to prevent insect pollination; www.britishcouncil.org 49 Science10GK5 Item identity AO1 AO2 AO3 AO4 Content Reference(s) Marks marks marks marks marks Science10GK51ai 3 3 aii aiii 10.1.22 Define primary Science10GK51b 2 producers, primary and 2 secondary consumers in food chains and webs Science10GK51c 2 2 9.9.7 Explain the impact of 4... agriculture on the environment in the form of pollution – …... pesticides and drugs used in farming poisoning animals because of bioaccumulation. Total marks 3 4 2 9 Item purpose The question assesses the understanding of the role of the decomposers in an ecosystem and the effects of using harmful chemicals on the environment. www.britishcouncil.org 50  Question(s) 1 Fig. 1 shows part of a desert food web. Fig. 1 1(a) Identify in Fig. 1.1: 1(a)(i) A producer (1 mark) 1(a)(ii) A primary consumer (1 mark) 1(a)(iii) A secondary consumer (1 mark) 1(b) Draw a food chain containing a snake. (2 marks) < 4 cm space > 1(c) Discuss the impact of pesticides on the food web in Fig.1. (4 marks) (Total marks 9) www.britishcouncil.org 51 Mark scheme 1 (a)(i) Identify in Fig. 1.1: A producer Answer Guidance Cactus 1 (a)(ii) Identify in Fig. 1.1: A primary consumer Answer Guidance insect / small lizard /rat ; 1 (a)(iii) Identify in Fig. 1.1: A secondary consumer Answer Guidance scorpion / large lizard / snake / falcon / fox 1 (b) Draw a food chain containing a snake. Answer Guidance All organisms; Arrows correct direction; i.e., Cactus -> rat -> snake 1 (c) Discuss the impact of pesticides on the food web in Fig.1. Answer Guidance Indicative science Kills insects Less food for scorpion / large lizard Less large lizards, less food for fox / falcon Bioaccumulation in top predator/falcon/fox Damage to offspring due to bioaccumulation Less damage to cacti from insects More food for small lizard / rat Change in populations of secondary consumers www.britishcouncil.org 52 Level of response Level Description Marks 4 Clear well-structured explanation linking effects to causes or 4 underpinning theory. 3 Clear description of relevant facts with some explanation relating 3 effects to causes or underpinning theory. 2 Description of the basic facts but no link of effects to causes or 2 underpinning theory. 1 Limited isolated descriptive points relevant to the topic 1 0 Nothing worthy of credit 0 www.britishcouncil.org 53 ScienceCKV4 Item identity AO1 AO2 AO3 AO4 Content Reference(s) Marks marks marks marks marks SCIENCECKV41a 2 10.5.19 Draw or interpret 2 a food chain or food web 10.1.22 Define primary producers, primary and secondary consumers in food chains and webs SCIENCECKV41b 1 10.5.19 Draw or interpret 1 a food chain or food web SCIENCECKV41c 4 9.9.7 Explain the impact 4 of...agriculture on the environment in the form of...... pesticides …... because of bioaccumulation. Total marks 1 2 4 7 Item purpose The question assesses the students’ knowledge about food chains and calculate energy at different levels in the food chain. Source(s) 1 Some information about a food chain is listed. Caterpillars are herbivores. Blackbirds eat secondary consumers. Eagles eat blackbirds. Spinach carries out photosynthesis. 1(a) Draw a food chain using all of the information. (2 marks) www.britishcouncil.org 54 1(b) What do the arrows in a food chain represent? (1 mark) 1(c) A farmer sprays their spinach with pesticide and kills most of the caterpillars. Some caterpillars survive. (4 marks) Discuss the impact on the food chain. (Total marks 7) Mark scheme 1 (a) Draw a food chain using all the information. Answer Guidance Correct sequence. Correct arrow direction, Spinach caterpillar blackbird eagle 1 (b) What do the arrows in a food chain represent? Answer Guidance the transfer of energy; from the producer to the consumer(s); 1 (c) Discuss the impact on the food chain. Answer Guidance Less food for blackbird / blackbirds die out; Less food for eagle / eagles die out; Pesticides in surviving caterpillars transfers to consumers; Bio-accumulation in consumers; www.britishcouncil.org 55 Science10PB1 Item identity AO1 AO2 AO3 AO4 Content Reference(s) Marks marks marks marks marks Science10PB1 1 10.1 1 Item purpose The question assesses Source(s) Source information: Own question Question(s) 1 Methane gas is burnt in air. State whether the reaction is exothermic or endothermic. (1 mark) Mark scheme 1 Methane gas is burnt in air. State whether the reaction is exothermic or endothermic. Answer Guidance It is exothermic reaction (1) www.britishcouncil.org 56 Science10PB6 Item identity AO1 AO2 AO3 AO4 Content Reference(s) Marks marks marks marks marks Science10PB6 1 10.1.1 Scientific 1 classification recognise the difference between reactions, such as, exothermic and endothermic, oxidation and reduction, etc. Item purpose The question assesses the students' learning and understanding about type of reaction. Source(s) Based on types of reactants and the product formed, there are different types of reaction Source information: Own question Question(s) 1 Which of the following reactions is exothermic? A. Quick lime is dissolved in water to produce slaked lime. B. Calcium carbonate is heated to produce carbon dioxide gas and quick lime. C. Lead nitrate is heated to produce lead oxide, nitrogen dioxide and oxygen. D. Mercuric oxide is heated to produce mercury and oxygen. (1 mark) Mark scheme 1 Which of the following reactions is exothermic? Answer Guidance A www.britishcouncil.org 57 Science10GD3 Item identity AO1 AO2 AO3 AO4 Content Marks marks marks marks marks Reference(s) Science10GD31a 3 10.4.1 Balance 3 chemical equations Science10GD31bi,bii,biii 3 3 Science10GD31ci 2 10.1.1 Define 2 types of chemical Science10GD31cii 3 3 reactions: Science10GD31d 1 combination, 2 decomposition, displacement, double displacement, precipitation, neutralization, oxidation and reduction. Total marks 2 11 13 Item purpose The question assesses the type of chemical reactions which underpin the characteristics of chemical reactions and potential impact on environments. Question(s) 1 The reaction between magnesium and oxygen produces magnesium oxide. Energy is released as heat and light during the reaction. 1(a) Complete and balance the symbol equation to show this reaction. Include the state symbols. Mg + O2 → (3 marks) www.britishcouncil.org 58 1(b) The reaction between magnesium and oxygen can be described in different ways. Explain why the reaction can be described as: i. a combination reaction. (1 mark) ii. an oxidation reaction. (1 mark) iii. an exothermic reaction. (1 mark) 1(c) Fig. 1 shows a piece of magnesium ribbon. Fig. 1 1(c)(i) Suggest why the surface of the ribbon must be cleaned before the (2 marks) ribbon is used. 1(c)(ii) Describe three other precautions that must be taken when burning magnesium. 1. __________ 2. __________ 3. __________ (3 marks) 1(d) Magnesium oxide dissolves in water to produce an aqueous solution. www.britishcouncil.org 59  Suggest the pH of the solution __________ Explain your answer (2 marks) (Total marks 13) Mark scheme 1 (a) Complete and balance the symbol equation to show this reaction. Include the state symbols. Answer Guidance Formulae; Balancing; State symbols; 2Mg (s) +O2 (g) → 2MgO (s) 1 (b) The reaction between magnesium and oxygen can be described in different ways. Explain why the reaction can be described as: i. a combination reaction. ii. an oxidation reaction. iii. an exothermic reaction. Answer Guidance (b)(i) more than one reactant and a single product; (b)(ii) oxygen is gained/added (by Mg); (b)(iii) heat is released; 1 (c)(i) Suggest why the surface of the ribbon must be cleaned before the ribbon is used. Answer Guidance to remove oxide/carbonate layer; ALLOW to remove Mg compounds www.britishcouncil.org 60 which prevent burning / to allow burning AW; 1 (c)(ii) Describe three other precautions that must be taken when burning magnesium. 1. __________ 2. __________ 3. __________ Answer Guidance Any three from: wear goggles hold in tongs / crucible do not observe the flame directly use a small amount Safety screen / tie hair back / heat proof mat 1 (d) Magnesium oxide dissolves in water to produce an aqueous solution. Suggest the pH of the solution __________ Explain your answer Answer Guidance 8 –10; metal oxides are basic; www.britishcouncil.org 61 Science10NG1 Item identity AO1 AO2 AO3 AO4 Content Reference(s) Mark marks marks marks marks Science10NG1 1 10.1.1 1 Item purpose The question assesses whether the student understands the concept of different types of reaction to identify the combination reaction. Source(s) NCERT TEXTBOOK FOR CLASS-X Ch-1 Chemical reactions and equations Question 1 A chemical reaction in which two or more substances combine to form a single product is A. a decomposition reaction B. a combination reaction C. a displacement reaction D. an exothermic reaction (1 mark) Mark scheme 1 A chemical reaction in which two or more substances combine to form a single product is A. a decomposition reaction B. a combination reaction C. a displacement reaction D. an exothermic reaction Answer Guidance B www.britishcouncil.org 62 Science10R5 Item identity AO1 AO2 AO3 AO4 Content Reference(s) Marks marks marks marks marks Science10R51a 4 10.1.1 Define types of 4 chemical reactions: Science10R51b 1 2 combination, decomposition, displacement, double displacement, precipitation, neutralization, oxidation and reduction. Total marks 4 1 1 5 Item purpose The question assesses …students' ability to define decomposition reaction. Effect of nature of water on electrolytic decomposition of water Question(s) 1 Decomposition is a type of chemical reaction. 1 (a) Using water as an example, state and explain what happens in electrolytic decomposition. (4 marks) 1 (b) Suggest why pure water does not undergo electrolytic decomposition. (1 marks) www.britishcouncil.org 63 Mark scheme 1 (a) Using water as an example, state and explain what happens in electrolytic decomposition. Answer Guidance Any four from: ALLOW reference to ions one reactant forms more than one (stable) product; (when) energy/electricity is supplied; hydrogen and oxygen; hydrogen released at cathode / oxygen released at anode. 1 (b) Suggest why pure water does not undergo electrolytic decomposition. Answer Guidance it is not ionic / no ions are present. ALLOW it is covalently bonded www.britishcouncil.org 64 Science10R1 Item identity AO1 AO2 AO3 AO4 Content