Investigative study in chemistry

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Investigative study in chemistry
Sophia Cheng 7 November 2007
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Investigative Study (IS)

• Conducted in groups of 3 to 5 students
• Provide students with opportunities to design and
  conduct an investigation with a view to solving
  an authentic problem
• Students will learn about scientific processes
  and how these processes work to generate new
  information

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Aims of investigative study

• Students can
• apply their knowledge and understanding of
  chemistry
• develop and apply various practical skills
• develop skills such as creativity, critical
  thinking, communication, problem-solving
• develop understanding on nature of science

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Before conducting IS, students should be guided
on

• How to work together in a group to develop an
  investigation plan and solve a problem
• How to define a researchable topic
• How to search for relevant information from
  various sources
• How to write an investigation plan
• How to write a laboratory report or make a poster
  for presentation

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• For learning and teaching
• Topic XVI in NSS Chemistry curriculum
• For assessment

Practical related task Practical related task Practical related task Non-practical related task
Basic Chemical Analysis Experiment Investigative Study Assignment
Weighting 20 30 30 20
S5 ?1 ?3 1 ?1
S6 ?1 ?3 1 ?1
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Implementation timetable of SBA
Year of examination Implementation of SBA
2012 2013 ?practical related tasks ?investigative study ?non-practical related tasks
2014 and thereafter ?practical related tasks ?investigative study ?non-practical related tasks
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Investigative study (20 hours)

• Design and conduct a first-hand investigation

(a) Searching for and defining questions 3 hrs
(b) Developing an investigative plan 4 hrs
(c) Conducting the investigation 6 hrs
(d) Organizing and analyzing data 4 hrs
(e) Presenting findings 3 hrs
1. Design
2. Process
3. Report
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Using the Allocated Lesson Time (20 hrs)
Sun Mon Tue Wed Thu Fri Sat
1 2 (a) 3 4 (a) 5 6
7 8 9 (b) 10 11 (b) 12 13
14 15 16 (b) 17 18 (c) 19 20
21 22 23 (c) 24 25 (c) 26 27
28 29 30 (c) 31
1 (c) 2 3
4 5 6 (d) 7 8 (d) 9 10
11 12 13 (d) 14 15 (e) 16 17
18 19 20 (e) 21 22 23 24
Double period (2 x 40 mins 1.3 hr) 2.67 hrs
/week 7.5 weeks
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Using post-examination school days
Sun Mon Tue Wed Thu Fri Sat
11 12 13 14 15 16 17
18 19 20 (a) 21 (b) 22 (c) 23 (c) 24
25 26 (d) 27 (e) 28 29 30
July 1
2 3 (a) (a) 4 (b) 5 6 (b) 7 8
9 10 (c) 11 (c) 12 (d) 13 (e) 14 15
16 17 (c) 18 (c) 19 (d) 20 21 (e) 22
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Implementation schedule
Pros Cons
Easter, Lunar New Year, Summer holiday -Reserve more time for teaching -Long practical section -Attendance problem -Extra workload -Extent of involvement
Post examination -Reserve more time for teaching -Long practical section -Attendance problem -Clash with other projects of different subjects
Normal school days -Complement to teaching -No attendance problem -Chopped practical sections -Too hectic
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Try-out Making Your Own Acid-Base Indicator

• Tasks
• Extract coloured pigments from plant materials
• Use the extract as acid-base indicator and find
  the concentration of alkali in oven cleaner

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(No Transcript)
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Finding information and planning
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Extraction of coloured pigments
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Choosing suitable indicators
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Choosing suitable indicators
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Find the concentration of alkali in oven cleaner
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Try-out Chemical cells

• Task
• 1. Make a chemical cell from household chemicals
  and materials
• 2. Test the performance of the chemical cell

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This chemical cell consists of 9 pairs of metal
couples. Its voltage is between 2 2.5V.
Coin Cell made by aluminium foil and coins.
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More examples

• Salt content of snack

• Gravimetric method
• Titrimetric methods
• Volhard method back titration of Ag with KSCN
  using Fe2 as indicator
• Mohr method titration with Ag using K2CrO4 as
  indicator

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Self-heating food/drink container
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Getting copper from its ore

1. To extract copper metal from a given ore sample
2. To isolate product
3. To calculate extraction efficiency
4. To calculate cost of the method

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Appropriateness of the Topic

• Does the activity address something worth
  learning?
• Is the topic socially relevant, interesting or
  motivating?
• Is the cognitive demand appropriate?
• Do students have the required prior knowledge and
  adequate skills?
• Are resources such as journal articles, reference
  books, chemicals and apparatus available?
• Is the time available sufficient for the
  activity?
• Are there any safety concerns?
• Can laboratory technicians and others help in its
  implementation?

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Your concerns

• 10 groups, 10 different projects
• Scale of investigation
• Laboratory safety
• Clash with investigation of other science
  subjects such as Physics
• Collaboration with lab tech and other teachers

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Discussion

1. When is the best time to implement IS? Why?
2. How will you allocate the 20 hours of IS in your
   teaching schedule?
3. How will you develop students skills and
   interests in conducting scientific inquiries?
4. What guidelines regarding IS will you give to
   students? How will you guide students to finish
   IS on schedule?

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1. What chemistry investigations do you think are
   suitable for IS?
2. How open will you let students decide their
   research questions?
3. How will you prepare yourself to implement IS?