Topic XVI Investigative Study in Chemistry (20 hours)
Chapter 3 Curriculum Planning
3.3 Curriculum Planning Strategies
3.3.1 Interface with the Junior Secondary Science Curriculum
This curriculum starts with the topic “Planet Earth” which helps students appreciate that the world is made up of chemicals, develop some basic knowledge of chemistry, acquire some fundamental practical skills and develop positive attitudes towards chemistry. Furthermore, through the study of the topic, students can consolidate their knowledge, understanding and skills of scientific investigation acquired in their junior secondary science courses. Unit 1
“Introducing Science” and the experience of undertaking scientific investigations in Science (S1-3) are relevant.
Knowledge and understanding of chemistry developed through the three-year junior secondary science courses are “stepping stones” towards senior secondary Chemistry.
Figure 3.3 shows how relevant chemistry topics in the Science (S1-3) Curriculum are related to different topics in this curriculum.
Science (S1-3) Chemistry
Unit Topic
2.1 The water cycle I. Planet earth
2.2 Dissolving 2.3 Water purification
2.4 Further treatment of drinking water
5.3 Energy sources V. Fossil fuels and carbon compounds
6.1 Particle theory II.
VI.
Microscopic world I Microscopic world II 6.2 Particle model for the three states of
matter 6.3 Dissolving
7.5 Balance of carbon dioxide and oxygen in Nature
I. Planet earth
7.6 Air quality XV. Analytical chemistry
9.1 Common acids and alkalis IV. Acids and bases 9.2 Measuring pH for acids and alkalis
9.3 Neutralisation
9.4 Corrosive nature of acids
9.5 Potential hazards related to the use of acids and alkalis
13.1 Atoms and elements II. Microscopic world I
13.2 Periodic Table
13.3 Mixtures and compounds I. Planet earth
13.4 Metals III. Metals
13.5 Materials of the modern world V.
XI.
XIV.
Fossil fuels and carbon compounds Chemistry of carbon compounds Materials chemistry
Figure 3.3 Relationship between Science (S1-3) Curriculum* and the Chemistry Curriculum
3.3.2 Suggested Learning and Teaching Sequences
The topics in compulsory and elective parts of the curriculum are listed in a possible sequence suitable for the majority of students (figure 3.4, sequence I). This sequence is organised in such a way that learning starts with topics with more concrete content, and then progresses onto topics that are more abstract. For instance, students are expected to start the curriculum with the topic “Planet Earth” which is designed to be a bridge between students’
junior secondary science courses and the Chemistry Curriculum. Then, students are expected to start learning the chemistry of matters like metals, acids and bases, and fossil fuels with which they are familiar in daily life. After that, students have to face the challenge of learning more abstract concepts in topics like “Redox reactions, chemical cells and electrolysis”, “Chemical equilibrium”, etc.
The learning sequence mentioned above is not intended to be the only one suitable for all schools. Alternative sequences with due regard to the interests, needs, prior knowledge and readiness of students can be adopted where appropriate. Some alternative learning and teaching sequences (sequences II and III) for the compulsory part are suggested in figure 3.4.
Year Sequence I Sequence II Sequence III
S4
Planet earth Planet earth Planet earth
Microscopic world I Microscopic world I Microscopic world I
Metals Metals Microscopic world II
Acids and bases Acids and bases Metals
Fossil fuels and carbon compounds
Chemical reactions
and energy Acids and bases
S5
Microscopic world II Rate of reaction Redox reactions, chemical cells and electrolysis
Redox reactions, chemical cells and electrolysis
Redox reactions, chemical cells and electrolysis
Fossil fuels and carbon compounds
Chemical reactions
and energy Microscopic world II Chemistry of carbon compounds
Rate of reaction Fossil fuels and carbon compounds
Chemical reactions and energy
Chemical equilibrium Chemistry of carbon
compounds Rate of reaction
Chemistry of carbon
compounds Chemical equilibrium Chemical equilibrium
Patterns in the chemical world Patterns in the chemical world
Patterns in the chemical world
Besides the suggestions mentioned above, teachers can also consider the following ideas.
(1) Curriculum organisation of knowledge and skills of “stoichiometry and mole”
Stoichiometry deals with the quantitative aspects of chemistry and is an emphasis within senior secondary Chemistry. Concepts related to stoichiometry and calculations related to mole, formula mass, empirical formula, molecular formula, molar mass, molarity and molar volume are introduced at different parts of this curriculum, and are organised in a progressive hierarchy. These practices help students to master concepts and acquire the skills to perform calculations without being loaded with a great deal of abstract and unfamiliar information. Teachers should provide opportunities that enable students to link these concepts and master the skills in a systematic way.
Figure 3.5 illustrates how the concepts related to stoichiometry and calculations related to mole are organised in this curriculum.
Figure 3.5 Organisation of Stoichiometry and Calculations Related to Mole
Avogadro's Constant
Mole
Calculations on titrations from chemical equations
Molarity Stoichiometry
Mass number
Isotopic masses
Relative atomic masses
Relative molecular masses and formula masses
Empirical formulae and molecular
formulae Percentage by mass
of an element in a compound
Molar mass
Reacting masses from chemical
equations
Molar volume of gases
Topic II Topic III Topic IV
Topic IX Topic III
Topic III
Alternatively, it is known that some teachers prefer to complete the study of calculations related to mole in a relatively short period of time, say before the end of S4. Such teachers can organise the subtopic “molar volume of gases” after topic IV in their teaching. This arrangement can be beneficial to some students as they can then concentrate their efforts on mastering concepts related to mole. However, it is unlikely that this arrangement would suit all students.
(2) Integration of Microscopic World I and II
The curriculum puts forward the idea of organising the learning and teaching of concepts related to the microscopic world into two separate topics (i.e. Microscopic world I and II) at different years of study. The purpose of this organisation is to avoid loading students with a large number of abstract concepts in a short period of time, particularly at the early stages of senior secondary learning. The organisation suggested provides an opportunity for students to revisit their learning in the previous year of study. However, some teachers may prefer to introduce the concepts related to structures and properties in one go, and believe that their students can benefit from this organisation. Such teachers can organise their own curriculum so that the topics “Microscopic world I and II” can be studied together. This kind of integration can be extended to topics like: “Fossil fuels and carbon compounds” and
“Chemistry of carbon compounds”; and “Metals” and “Redox reactions, chemical cells and electrolysis”.
(3) Integration of the investigative study with elective topics
If students have a strong interest in chemical analysis and intend to carry out investigative study with more emphasis on analytical chemistry, teachers can organise the learning of the elective topic “Analytical chemistry” in parallel with the Investigative Study. This organisation helps students to apply the concepts of analytical chemistry to solve problems, and at the same time to develop various skills expected (please refer to “Investigative study in chemistry” in Chapter 2 for details). Furthermore, teachers can also adopt a problem-based approach by posing challenging problems to students. By solving the problems through gathering information, reading critically, learning new knowledge on their own, discussion, experimentation, etc., students can master the knowledge and understanding required in the topic “Analytical chemistry”, and acquire relevant skills expected in the “Investigative study in chemistry”. This kind of integration can be extended to other elective topics including
“Industrial chemistry” and “Materials chemistry”.
(4) Organisation within a topic
Further to the suggested integration of major topics listed above, teachers can also arrange different sequences for learning and teaching within a topic for their students. For instance, in “Microscopic world I”, the teacher can start with the more concrete ideas related to properties of substances and then move on to the more abstract concepts of chemical bonding.
Two possible sequences are outlined in figure 3.6.
Sequence A Sequence B
a. Atomic structure a. Atomic structure
b. The Periodic Table b. The Periodic Table
d. Structures and properties of metals e. Ionic and covalent bonding
c. Metallic bonding c. Metallic bonding
f. Structures and properties of giant ionic substances
f. Structures and properties of giant ionic substances
e. Ionic bonding d. Structures and properties of metals
g. Structures and properties of simple molecular substances
g. Structures and properties of simple molecular substances
e. Covalent bonding h. Structures and properties of giant covalent substances
h. Structures and properties of giant covalent substances
i. Comparison of structures and properties of important types of substances
i. Comparison of structures and properties of important types of substances
Figure 3.6 Possible Learning and Teaching Sequence for Topic II
It is possible to attain the learning targets associated with the subtopic “Industrial Processes”
in Topic XIII, for example, in two different ways. The first approach is to provide all the foundation knowledge and concepts required prior to an in-depth treatment of the prescribed industrial processes. The second approach, the application-first approach, is to study the industrial processes as the central theme, while knowledge, understanding and ideas emerge and are learnt along the way. The two possible approaches are depicted below.
Figure 3.7 Possible Learning and Teaching Approach for Topic XIII
3.3.3 Curriculum Adaptations for Learner Diversity
Teachers must design and deliver a curriculum in line with the different interests and abilities of their students. Teachers may need to design and implement a curriculum for students who can only master part of the concepts and skills described in this Guide, while teachers of more able students may have to devise more complex learning and activities that challenge them at greater depth. This curriculum has been designed flexibly with this in mind, and is intended to serve as a reference rather than a prescription.
This curriculum can be adapted in a number of ways such as focusing learning only on the topics in the compulsory part and putting less emphasis on topics in the elective part.
Teachers can reflect on the following suggestions when planning how to design a school-based curriculum for students with different needs.
(1) If students have difficulty in mastering the whole curriculum, teachers and students can work out the appropriate level of study for the topics in the compulsory part.
Listed below are some topics of the compulsory part with subtopics which are considered to be cognitively more demanding, i.e. students may need extra support to master the knowledge and understanding in these topics:
Microscopic world II
Chemical reactions and energy
Chemical equilibrium
Chemistry of carbon compounds
Rate Equation
Activation
Energy Catalysis Industrial Processes
(Haber Process) Sequence A
Rate Equation Activation
Energy
Catalysis Industrial Processes (Haber Process) Sequence B
(2) Where students have difficulty in coping with the whole curriculum, teachers and students can discuss and agree on alternative arrangements like putting only a minimum of effort into study of the topics of the elective part, or skipping the study of the elective part altogether.
In brief, teachers are encouraged to design their curriculum to cater for diversity among their students and to evaluate it against the design principles described in Chapter 2.
3.3.4 Flexible Use of Learning Time
As mentioned in Chapter 2, a total of 250 hours or 10% of total senior secondary lesson time should be allocated to cover this curriculum. Teachers are encouraged to use this time flexibly to help students attain all the learning targets of the curriculum. More or less time may be allocated to particular topics in line with student interests and abilities. Schools may allocate more learning time for the study of the compulsory part to ensure students are equipped with sound fundamental knowledge and skills before starting the elective part.
Concerning the 20 hours allocated to the Investigative Study, teachers can allocate the time available flexibly to promote students’ learning and to develop the full range of abilities.
Lastly, schools are also encouraged to include half-day or whole-day activity sessions in the time-table, to allow continuous stretches of time for visits, scientific investigations outside the school, or other life-wide learning activities that can enhance the effectiveness of learning in chemistry.