NSS Integrated Science Public Assessment

1. NSS Integrated SciencePublic Assessment Mr Pau Chiu Wah Senior Manager Hong Kong Examinations and Assessment Authority

2. Public Assessment

3. Public Assessment

4. Public Assessment

5. School Based Assessment

6. SBA – Practical Related Tasks • Accuracy in measurement • Control of variables • Data collection • Safety awareness • Handling of apparatus Area A – abilities to be assessed

7. SBA – Practical Related Tasks • Planning of experiment • Precision in recording of data • Treatment and interpretation of data • Summarization of findings • Report writing Area B – abilities to be assessed

8. School-Based Assessment Practical Related Tasks

9. SBA - Non-Practical Related Tasks • Data analysis and interpretation • Poster presentation • Development of multimedia artifact • Commentary/reflection of articles • Small-scale projects Examples:

10. SBA

11. Tasks ahead • Sample question papers and trial tests • SBA tasks and assessment rubrics • Development of level descriptors and validation

12. Sample Question Papers (Under Construction)

13. Water is the most abundant compound on planet Earth, covering nearly three-quarters of its surface. Liquid water has many unusual properties. Both its specific heat capacity (4.18 J g–1 K–1) and its specific heat of vaporization (2250 J g–1) are almost highest among all common liquids. Its maximum density occurs at 4oC. These and other properties of water can provide reasons why water is important to life. (a)Explain, in molecular terms, why liquid water has a high specific heat capacity among all common liquids. (3 marks) Form and function Apply scientific knowledge, concepts and principles to explain phenomena and observations, and to solve problems (b)

14. (b) Suggest why the following properties of water are important to life.  (i) Water has a high specific heat capacity.  (ii) The maximum density of water occurs at 4 oC. (4 marks) (c)Water plays an important role in moderating the climate of our planet.Discuss how the following occurrence of water can moderate our climate:  (i) water vapour in the atmosphere  (ii) water in the oceans(4 marks) Evidence, models & explanation Apply scientific knowledge, concepts and principles to explain phenomena and observations, and to solve problems (b)

15. (d) A simplified map of Country C is shown below. The river provides the major source of fresh water to this country.

16. Health problems in both City A and City B were reported to be on the rise over the years. Examination of the quality of fresh water supply to both cities revealed that water supplying City A had high levels of cadmium and zinc, while that supplying City B had high levels of E. coli, inorganic phosphates and nitrates. • Referring to the map, suggest probable causes for the contamination of fresh water supplying City A and City B. Recall and show understanding of facts, concepts and principles of science, and the relationships between different topic areas in the curriculum framework(a) Analyse and interpret both numerical and non-numerical data in forms such as continuous prose, diagrams, photographs, charts and graphs – and make inferences and logical deductions, and draw conclusions from them (g)

17. (ii) The government of this country is debating on whether hydroelectric power (HEP) should be adopted as an energy source. A proposal has been made to build a dam at site D for the provision of HEP.  (I) Give two advantages of using HEP over the combustion of fossil fuel in generating electricity Recall and show understanding of facts, concepts and principles of science, and the relationships between different topic areas in the curriculum framework (a)

18. (II) Referring to the map, state two concerns regarding the proposal of building the dam at site D. (10 marks) Science, Technology, Society and Environment Analyse and interpret both numerical and non-numerical data in forms such as continuous prose, diagrams, photographs, charts and graphs – and make inferences and logical deductions, and draw conclusions from them (f) Show awareness of the ethical, moral, social, economic and technological implications of science, and critically evaluate science-related issues (j)

19. Energy, Weather and Air Quality (E1)

20. Fill in the blanks For the formation of a tropical cyclone, the ocean surface temperature must reach _______C or above, and there must be plenty of ____________________ evaporated from the ____________________. (3 marks) Suggested answers: 26.5 (1), water vapour (1), ocean (1)

21. Assume a typhoon moved towards the northwest of Hong Kong, crossed Hong Kong and made landfall over Guangdong (廣東). Put the following sentences in the right order to best describe the weather conditions of Hong Kong during the period. a. Cloudy or raining. Wind speed decreases b. Cloudy or raining. Wind speed increases c. Heavy rainfall with northeasterly wind, reaching hurricane force d. Hot and hazy e. Very low surface pressure and short period of relatively calm weather f. Heavy rainfall with southwesterly wind, reaching hurricane force (3 marks) Suggested answer: d → b → c → e → f → a

22. Multiple-choice Questions (Paper 2 Section A)

23. Non-practical Related Tasks Data analysis and interpretation

24. Study the information given below and answer the questions that follow: Fig 4.1: Number of Digital Mobile Phone Users in Hong Kong from 1993 to 2004 (Source: http://www.ofta.gov.hk/en/datastat/hktelecom-indicators_summary.html)

25. Passage 4.2: An excerpt adapted from a newspaper: Brain cancer cases doubled in 11 years. With the widespread use of mobile phones, the number of reported cases of brain cancer almost doubled in 11 years. It raises concerns about the possible development of brain cancer caused by the use of mobile phones.   According to official figures, there were only 517 cases diagnosed as brain cancers in 1991 in public hospitals, but the number of cases rises to 1532 in 2002 showing a sharp increase of 196%. ………… Cautious mobile phone buyers should make reference to the Specific Absorption Rate (SAR), which is a scale for measuring the rate at which electromagnetic radiation energy is actually absorbed by tissue of a human body, in watts per kilogram units (W/kg). The larger the SAR value, the more radiation is absorbed by human tissue.   The accepted limit of SAR in Europe is 2.0 W/kg, while that in America and Australia is 1.6 W/kg.

26. Table 4.3:Results from a Research to Study the Absorption of Electromagnetic Radiation by Tissues near Human Skull of People Using Mobile Phones

27. Possible adverse health effect caused by electromagnetic radiation emission from mobile phones has become a controversial issue in recent years. There are concerns about the risk of brain cancer caused by human head’s absorption of the electromagnetic radiation while using mobile phones. A lot of research has been done on investigating possible health risks caused by using mobile phones, but there are no conclusive results. (a)(i) With reference to Figure 4.1, suggest why very few research of such type was carried out before 1995. Analyse and interpret both numerical and non-numerical data in forms such as continuous prose, diagrams, photographs, charts and graphs – and make inferences and logical deductions, and draw conclusions from them (f)

28. (ii) Suggest why many of such research were conducted by manufacturers of mobile phones. Show awareness of the ethical, moral, social, economic and technological implications of science, and critically evaluate science-related issues (j) (iii) It may take many years to get definite results on whether mobile phone would cause health effects on users. Explain why. (4 marks) Apply scientific knowledge, concepts and principles to explain phenomena and observations, and to solve problems (b)

29. (b) After reading the newspaper article (passage 5.2), Fiona made the following statement: 'There is sufficient evidence to support the claim that brain cancer is caused by the use of mobile phones because during the same period, the number of mobile phone users also increased sharply.' Explain whether you agree with Fiona. (2 marks) Thinking Processes of science Formulate arguments, justify claims, evaluate evidence and detect errors (g)

30. (c) Suppose that you are the spokesman of the Office of Telecommunications Authority (OFTA), write a simple statement to explain to the general public the relationship between the thickness of skull and SAR. (1 mark) Analyse and interpret both numerical and non-numerical data in forms such as continuous prose, diagrams, photographs, charts and graphs – and make inferences and logical deductions, and draw conclusions from them (f)

31. (d)(i) Using the data given in Table 4.3, plot the SAR against age in the graph provided below. Present data in various forms, such as tables, graphs, charts, drawings, diagrams, and transpose them from one form into another (e)

32. (ii) What is the rate of energy absorption if a child of age 8 weighs 30 kg uses a mobile phone? Analyse and interpret both numerical and non-numerical data in forms such as continuous prose, diagrams, photographs, charts and graphs – and make inferences and logical deductions, and draw conclusions from them (f) (iii) If the acceptable SAR limit is 2.0, at what age would you advise a child to use a mobile phone? (5 marks) Make suggestions, choices and judgments based on scientific knowledge and principles (k)

33. Non-practical Related Tasks (Communication of Ideas)

34. Scientists communicate in a number of ways including: • Publication in research journals • Presenting papers at scientific conferences • Poster presentations at conferences • Book reviews by other scientists • Publication on the Internet • Sales brochures • Advertising flyers • Television documentaries (Dorothy Warren: The nature of science, Royal Society of Chemistry (2001))

35. Thank you