Chemistry Unit 4: How are carbon-based compounds designed for purpose?

Prerequisites

Chemistry Unit 3. Mathematical Methods is strongly recommended.

Course Description

Carbon is the basis not only of the structure of living tissues but is also found in fuels, foods, medicines, polymers and many other materials that we use in everyday life. In this unit students investigate the structures and reactions of carbon-based organic compounds, including considering how green chemistry principles are applied in the production of synthetic organic compounds. They study the metabolism of food and the action of medicines in the body. They explore how laboratory analysis and various instrumentation techniques can be applied to analyse organic compounds in order to identify them and to ensure product purity.

Students conduct practical investigations related to the synthesis and analysis of organic compounds, involving reaction pathways, organic synthesis, identification of functional groups, direct redox titrations, solvent extraction and distillations.

Areas of Study

How are organic compounds categorised and synthesised?

In this area of study students focus on the structure, naming, properties and reactions of organic compounds, including the chemical reactions associated with the metabolism of food. They explore how synthetic organic compounds can be produced more sustainably for use in society.

The selection of learning contexts should allow students to develop practical techniques to investigate organic structures and reactions. Students develop their skills in the use of scientific equipment and apparatus. They may construct models to explore organic structures, including isomers. Students may compare the properties of biodiesels produced using different oils, or may investigate organic reaction pathways such as the synthesis of esters used in food flavourings. They may investigate food metabolism by hydrolysing different types of plant starches. Students respond to challenges such as how to improve the atom economy of a selected chemical reaction or reaction pathway.

How are organic compounds analysed and used?

In this area of study students focus on laboratory and instrumental analyses of organic compounds, and the function of some organic compounds as medicines. They use distillation to separate mixtures, use volumetric analysis to calculate redox quantities, and explore how instrumental analysis is used to ensure the quality of consumer products. Students explain how some medicines that bind to the active sites of enzymes function by inhibiting the enzymes’ mode of action.

How is scientific inquiry used to investigate the sustainable production of energy and/or materials?

Students undertake a student-designed scientific investigation in either Unit 3 or Unit 4, or across both

Units 3 and 4. The investigation involves the generation of primary data related to the production of energy and/or chemicals and/or the analysis or synthesis of organic compounds, and should be inspired by a contemporary chemical challenge or issue. The investigation draws on knowledge and related key science skills developed across Units 3 and 4 and is undertaken by students in the laboratory and/or in the field.

When undertaking the investigation students are required to apply the key science skills to develop a question, state an aim, formulate a hypothesis and plan a course of action to answer the question, while complying with safety and ethical guidelines. Students then undertake an experiment to generate primary quantitative data, analyse and evaluate the data, identify limitations of data and methods, link experimental results to scientific ideas, discuss implications of the results, and draw a conclusion in response to the question. The presentation format for the investigation is a scientific poster constructed according to the structure outlined on page 14. A logbook is maintained by students for recording, assessment and authentication purposes.

Assessment

Outcomes	Assessment Tasks	Marks Allocated
Outcomes	(school-assessed coursework)	Marks Allocated
Analyse the general structures and reactions of the major organic families of compounds, design reaction pathways for organic synthesis, and evaluate the sustainability of the manufacture of organic compounds used in society	For each outcome, one task selected from: comparison and evaluation of chemical concepts, methodologies and methods, and findings from at least two practical activities analysis and evaluation of primary and/or secondary data, including identified assumptions or data limitations, and conclusions problem-solving, including calculations, using chemistry concepts and skills applied to real-world contexts analysis and evaluation of a chemical innovation, research study, case study, socio-scientific issue, or media communication. Each task type can be selected only once across Units 3 and 4. At least one of the four tasks should include reference to sustainability.	40
Apply qualitative and quantitative tests to analyse organic compounds and their structural characteristics, deduce structures of organic compounds using instrumental analysis data, explain how some medicines function, and experimentally analyse how some natural medicines can be extracted and purified.		40
Design and conduct a scientific investigation related to the production of energy and/or chemicals and/or the analysis or synthesis of organic compounds, and present an aim, methodology and method, results, discussion and conclusion in a scientific poster.	Communication of the design, analysis and findings of a student-designed and student-conducted scientific investigation through a structured scientific poster and logbook entries. The poster should not exceed 600 words.	40
Total Marks		120

Practical Work and Assessment  

Practical work is a central component of learning and assessment and may include activities such as laboratory experiments, fieldwork, simulations and other direct experiences as described in the scientific investigation methodologies on page 13. A minimum of 10 hours of class time should be devoted to student practical activities and investigations across Areas of Study 1 and 2. For Area of Study 3, a minimum of 10 hours of class time should be devoted to designing and undertaking the student-designed scientific investigation and communicating findings.

Overall Final Assessment

Graded Assessment	Title	Assessment	Exam Duration	Contribution to Study Score (%)
1	Unit 3 Coursework	School-assessed		20
2	Unit 4 Coursework	School-assessed		30
3	Written Examination	November	2.5 hours	50