Investigative study in chemistry

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

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

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

• For learning and teachingTopic XVI in NSS Chemistry curriculum

• For assessment

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

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

Implementation timetable of SBA

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

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

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

Implementation schedulePros 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

Try-out: Making Your Own Acid-Base Indicator

Tasks:1. Extract coloured pigments from plant materi

als

2. Use the extract as acid-base indicator and find the concentration of alkali in oven cleaner

Finding information and planning

Extraction of coloured pigments

Choosing suitable indicators

Choosing suitable indicators

Find the concentration of alkali in oven cleaner

Try-out: Chemical cells

Task:

1. Make a chemical cell from household chemicals and materials

2. Test the performance of the chemical cell

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.

More examples

Salt content of snack

(a)(a) Gravimetric methodGravimetric method(b)(b) Titrimetric methods:Titrimetric methods:

• Volhard method: back titration of AgVolhard method: back titration of Ag++ with KSCN using Fe with KSCN using Fe2+2+ as ind as indicatoricator

• Mohr method: titration with AgMohr method: titration with Ag++ using K using K22CrOCrO44 as indicator as indicator

Self-heating food/drink container

Getting copper from its ore

1.To extract copper metal from a given ore sample

2.To isolate product3.To calculate

extraction efficiency

4.To calculate cost of the method

CuCO3.Cu(OH)2.H2O(s)

CuO(s) CuSO4(aq)

Cu(s)

heat H2SO4(aq)

C(s), H2(g) or Town gas Zn(s) or electrolysis

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?

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