Chemistry is a cornerstone of scientific education, and mastering it can open doors to numerous exciting career paths. Whether you are aspiring to become a medical professional, environmental scientist, or chemical engineer, performing well in your WACE Chemistry exam is crucial for achieving your goals.
In this blog post, we'll dive deep into the WACE Chemistry syllabus, explore the exam format, and provide you with invaluable tips to boost your performance. From understanding what constitutes an 'A' grade to common pitfalls to avoid, we've got you covered.
So, grab your periodic table and put on your lab coat (metaphorically, of course) as we embark on this journey to Chemistry exam success in Western Australia!
Summary of Units
Unit 3
This unit explores the chemistry of oils and their environmental impact. Students study crude oil composition, various oils and polymers, and their applications. The unit emphasises sustainable chemistry practices, including recycling and waste management.
It highlights how chemistry contributes to environmental protection through innovations like biodegradable materials. Students also consider the broader implications of scientific knowledge in addressing real-world challenges.
Science Inquiry Skills
• construct questions for investigation; propose hypotheses; and predict possible outcomes
• plan investigations, including the procedure(s) to be followed, the materials required, and the type and amount of data to be collected; assess risk and address ethical issues associated with these methods
• conduct investigations, appropriate to the chosen context(s), safely, competently and methodically for the collection of reliable data, including the chemical identification of saturated and unsaturated compounds and the production and testing of a simple polymer, for example, casein glue or slime or similar
• represent data in meaningful and useful ways; organise and analyse data to identify trends, patternsand relationships; qualitatively describe sources of measurement error and inconsistencies in data; and use evidence to make and justify conclusions• interpret a range of scientific and media texts, and evaluate the conclusions by considering the quality of available evidence
• construct and use appropriate representations, to communicate conceptual understanding, solve problems and make predictions
• communicate scientific ideas and information for a specific purpose using appropriate language,nomenclature and formats, including scientific reports
Science as a Human Endeavour
• most hydrocarbon fuels produced from crude oil also contain sulfur. When a fuel burns in air, gases, such as carbon dioxide, sulfur dioxide and oxides of nitrogen, are released into the atmosphere. Solid particles may also be released. The burning of hydrocarbon fuels contributes to acid rain, global warming and global dimming. Technology has been developed to chemically remove sulfur dioxide from waste gases after combustion in power plants and international cooperation has resulted in industrialised countries reducing emissions of greenhouse gases, such as carbon dioxide
• biofuels, such as biodiesel and ethanol, are produced from plant material. The production of biofuels is sustainable and biofuels produce fewer pollutants than hydrocarbon fuels made from crude oil. There are economic, ethical and environmental issues surrounding the use of biofuels, for example, using cropland to grow crops for fuel rather than for food may have an impact on the cost of food or lead to food shortages
• many polymers are not biodegradable. Non-biodegradability can lead to problems with waste disposal and recycling. Some products, such as plastic bags, packaging and disposable cutlery, are being made from a combination of polymers and other additives, such as starch, so that they break down more easily. The use of these products may provide benefits, such as reduced green-house gas emissions and reduced use of crude oil substances. The benefits need to be offset against any increased costs in production.
Science Understanding
Crude oil
• crude oil is a mixture of a very large number of compounds• the substances in crude oil can be separated using fractional distillation
• crude oil is made up of hydrocarbons; hydrocarbons consist of only hydrogen and carbon atoms
• most of the hydrocarbons found in crude oil are called alkanes; alkanes are hydrocarbons that containonly single carbon to carbon bonds and are described as saturated
• alkanes can be named using IUPAC conventions (C1 –C8, straight chain only)
• alkanes can be represented using structural formula (C1 –C8, straight chain only) for example, propane (C3H8)
• some properties of hydrocarbons, for example, boiling point and viscosity, depend on the number of atoms in the hydrocarbon; these properties influence how hydrocarbons are used as fuels and lubricants
Other substances from crude oil
• substances separated from the fractional distillation of crude oil can be broken down (cracked) to make smaller hydrocarbons, such as alkenes
• alkenes are hydrocarbons that contain at least one carbon to carbon double bond and are described as unsaturated
• alkenes can be named using IUPAC conventions (C2-C3 only)
• alkenes can be represented using structural formulae (one double bond), for example, propene (C3H6)
Polymers
• alkenes can be used to make very large molecules called polymers, for example, polyethene and polypropene and polystyrene
• many small molecules, called monomers, are joined together to form polymers
• polymers have many useful applications, for example, plastics, water saving hydrogels, encapsulated microbes, and waterproof coatings for fabrics
• information on plastic packaging identifies the type of plastic and recycling process used
Vegetable oils
• some fruits, seeds and nuts are rich in oils that can be extracted
• vegetable oils are important foods and fuels as they provide a lot of energy
• oils are insoluble in water; oils can be used to produce emulsions, for example, in food and cosmetics
• vegetable oils that are unsaturated contain double carbon to carbon chemical bonds; these can bedistinguished using bromine water or a dilute solution of iodine in ethanol
Biofuels
• vegetable oils can be used to make biofuels
• ethanol is an alcohol with the formula CH3CH2OH
• ethanol can be used as a biofuel
• ethanol can be produced by fermentation
Unit 4
This unit covers two main areas of chemistry. The first part focuses on metals, examining their properties, extraction, uses, and the effects of corrosion. The second part explores biochemistry, particularly proteins, carbohydrates, and ATP.
Students learn about the roles of these molecules in the human body, including their function during exercise. The unit also investigates enzymes and how environmental factors affect their activity. Overall, this unit connects chemical principles to real-world applications in materials science and biology.
Science Inquiry Skills
• construct questions for investigation; propose hypotheses; and predict possible outcomes
• plan investigations, including the procedure(s) to be followed, the materials required, and the type and amount of data to be collected; assess risk and address ethical issues associated with these methods
• conduct investigations, appropriate to the chosen context(s), safely, competently and methodically for the collection of reliable data
• represent data in meaningful and useful ways; organise and analyse data to identify trends, patterns and relationships; qualitatively describe sources of measurement error and inconsistencies in data; and use evidence to make and justify conclusions
• interpret a range of scientific and media texts, and evaluate the conclusions by considering the quality of available evidence
• construct and use appropriate representations, to communicate conceptual understanding, solve problems and make predictions
• communicate scientific ideas and information for a specific purpose using appropriate language,nomenclature and formats, including scientific reports
Science as a Human Endeavour
Materials chemistry
• Aboriginal Peoples mined a variety of ochres, which contained mixtures of hydrated oxides of iron. The ochre and water was mixed into a paste and then formed into blocks for ease of transport. The pigments were made by grinding the ochre to a powder and mixing it with a fluid, for example, saliva. Aboriginal Peoples used the pigments from the ochre to paint their bodies, implements and caves.Ochre was extensively traded; red ochre was particularly valuable as it symbolises the blood of ancestral beings
• shape memory alloys (SMAs) are metals that can return to their original shape after being deformed. This allows them to be used as actuators in many applications, such as in fire sprinkler systems, anti-scalding valves in showers and guide wires in dental braces
• the extraction of metals from ores involves the use of limited resources and is expensive in terms of energy and effects on the environment. New ways of extracting copper from low grade ores, for example bioleaching and phytomining, are being researched to limit the environmental impact of traditional mining methods
• almost all engineering materials, for example steel, are subject to corrosion. Corrosion can result in train derailments, collapsed bridges and power outages. Due to the economic costs involved, corrosion research groups collaborate to develop new treatment methods and structural design features to reduce the amount of corrosion
Biochemistry
• a knowledge of the chemical reactions that occur in the human body is used in the field of pathology. Body fluid samples, for example, blood and urine, can be analysed for a range of chemical substances using a variety of analytical techniques. If the concentration of the chemical substance being analysed is not within the normal range, it may indicate that a particular organ, for example the liver or kidney, is not functioning correctly, or that disease is present
• in people with diabetes, insulin (a protein hormone) is no longer produced or not produced in sufficient amounts by the pancreas. Insulin helps convert glucose in the blood into glycogen for storage in the liver and muscles. Diabetics regularly monitor their blood glucose levels to ensure that they are not too high. Blood glucose monitoring involves diabetics pricking their finger to obtain a blood sample. Inconvenience, sore fingers, and a fear of needles may cause diabetics to not regularly monitor glucose levels. Emerging technologies, for example, smart phone apps, help calculate insulin dosage. Non-invasive products, such as ring-shaped probes which are placed on the outside of the finger, help diabetics to monitor their glucose levels
• sports drinks and diet supplements are formulated using a knowledge of biochemistry. The composition and form of sports drinks and diet supplements is changed by manufacturers in response to new scientific information becoming available, as well as in response to social, economic and ethical considerations
• performance enhancing drugs, for example, a protein hormone, erythropoietin (EPO), can increaseoxygen delivery to the muscles, improving their endurance capacity. The use of banned performanceenhancing drugs in sports provides an unfair advantage. Their use can result in health complications, for example, stroke. The decision by athletes to take performance enhancing drugs may be influenced by social, economic, ethical and political considerations
Science Understanding
Materials chemistry
Metal properties and structure
• metals can be distinguished from non-metals by their physical and chemical properties
• metals and non-metals can be identified by their position on the periodic table
• metals consist of giant structures of atoms arranged in a regular pattern
• the layers of atoms in metals are able to slide over each other, so metals can be bent and shaped
• metals have a range of melting points and relatively high boiling points
• different metals have different abilities to conduct heat and electricity
• conductivity depends on the ability of electrons to move throughout the metal
• electrical conductivity can be measured using a simple circuit or one which could include an ammeter or a multimeter
• the properties of metals determine how they are used, for example, copper is useful for electrical wiring and plumbing
• flame tests can be used to identify metals
• transition metals form coloured compounds; this enables them to be used for many purposes, for example, paint pigments , coloured glass and ceramics
Alloys
• metals can form mixtures with other metals and substances like carbon to make alloys, for example, stainless steel
• alloys have different physical properties when compared to pure metals; this can increase the range of purposes that an alloy is suitable for
Metal reactions
• observations, word equations and simple chemical equations for the following chemical reaction types:
▪ acid-metal
▪ metal carbonate decomposition
▪ simple metal displacement
• metal/metal ion displacement reactions can be used to investigate differences in metal reactivity
Metal extraction
• nonreactive metals, for example gold, are found in the Earth as the metal itself, but most metals are found as compounds
• copper can be extracted from ores• the percentage of metal in an ore can be calculated from the mass of the metal in the ore and the mass of the ore sample• copper can be obtained from solution by electrolysis, or by displacement using iron
Metal corrosion
• corrosion is the gradual break down of materials by chemical reaction with the environment
• corrosion occurs when metals react with oxygen to form metal oxides, for example, aluminium and iron
• when aluminium reacts with oxygen, the resulting aluminium oxide forms a tough coating that protects the metal underneath from further contact with oxygen
• when iron reacts with oxygen and water, it forms a corrosion product called rust. Rust on the surface of the iron is porous, allowing the metal underneath to come into further contact with oxygen and water
• the rate of corrosion of iron can be influenced by a number of factors, for example, moisture andimpurities
• the rate of corrosion of iron can be slowed down when it is alloyed with other metals, in contact with a more reactive metal, or when it has a protective coating
Biochemistry
Proteins
• proteins are large molecules (polymers) made up from smaller molecules (monomers) called amino acids
• amino acids consist mainly of carbon, hydrogen and nitrogen atoms and sometimes sulfur atoms
• there are many different types of proteins that carry out different functions, for example:
▪ structural proteins (protection, support, movement), for example, hair and muscle
▪ enzymes (biological catalysts), for example, amylase, catalase and pepsin
▪ hormones (regulation of body functions), for example, insulin
▪ transport (movement of molecules in body), for example, haemoglobin
▪ the catalytic activity of enzymes is dependent on temperature and pH
Carbohydrates
• carbohydrates consist of carbon, hydrogen and oxygen atoms• carbohydrates are stored as glycogen in the muscles and liver
• glycogen is a large molecule (polymer) made up from smaller molecules (monomers) of glucose
• glucose is the main source of energy in the diet, in preference to fats and proteins
During exercise
• glycogen is broken down to form glucose
• cellular respiration is a chemical reaction that takes place in the cells of the body to produce energy. Cells use adenosine triphosphate (ATP) from glucose and oxygen to supply their energy needs
• cellular respiration requires oxygen to generate ATP and is also called ‘aerobic respiration’
• cellular respiration can be represented using a simple word equation
• muscles are made up of multiple bundles of muscle fibres (cells) held together by connective tissue
• skeletal muscle fibres can be classified into two broad categories, Type I and Type II
• Type I muscle fibres appear red due to the presence of a protein (myoglobin) which binds oxygen; Type II muscle fibres appear white as they lack this protein
• ATP is used up when muscles move and contract
• endurance exercise uses mainly Type I muscle fibres and involves aerobic respiration
• exercise that involves short bursts of speed and power, for example sprinting, uses mainly Type IImuscle fibres and involves anaerobic respiration
• anaerobic respiration produces ATP from the breakdown of glucose without the presence of oxygen
• lactic acid is produced by anaerobic respiration and accumulates in muscle cells. This causes a decrease in the pH of the muscle cells, leading to an impairment of muscle contractions
• ions (electrolytes) must be present in appropriate concentrations to maintain muscle contraction and fluid balance• sweating causes loss of water which can lead to dehydration and the excretion of ions (electrolytes) for example, sodium, potassium, magnesium and chloride ions
💡 Study tip! Organise your notes by the headers and sub-headers in the syllabus. This ensures you cover everything that could be on the exam and keeps your notes super organised.
Format of the WACE Chemistry Exam
The school-based assessment for the Chemistry course consists of four types of assessment:
- Science Inquiry (40%)
- Includes practical work and investigations
- Activities may involve practical tests, modelling, simulations, and data analysis
- Investigations are more extensive and can include experimental testing and scientific reports
- Should be conducted in a supervised classroom setting
- Extended Response (20%)
- May involve selecting and interpreting scientific and media texts
- Can include evaluating processes, claims, and conclusions
- May take the form of answers to specific questions based on individual research
- Strategies should be used to authenticate out-of-class work
- Test (25%)
- Typically includes multiple choice questions and questions requiring short and extended answers
- Conducted in supervised classroom settings
- Externally Set Task (15%)
- A written task or set of items developed by the School Curriculum and Standards Authority
- 50 minutes duration
- Administered by the school in Term 2
Key points:
- Each assessment type must be included at least once over the year
- The set of tasks must provide a representative sampling of the content for Units 3 and 4
- Teachers must develop an assessment outline that includes a set of assessment tasks
- The outline should include task descriptions, unit content to be assessed, weightings, and approximate timing
- Appropriate validation/authentication processes are required for tasks not administered under test conditions
💡 Take notes efficiently and effectively using these tips!
What Does an 'A' Look Like?
An 'A' grade in WACE Chemistry represents excellent achievement. Here's a detailed breakdown of what's expected for an 'A' grade:
How to Do Well in WACE Chemistry
To excel in your WACE Chemistry consider the following strategies:
- Master the Fundamentals
- Review and solidify your understanding of basic chemical concepts from previous years.
- Pay special attention to the language of chemistry, differences between elements, compounds, and mixtures, and basic chemical reactions.
- Develop Strong Conceptual Understanding
- Focus on understanding chemical models and principles, not just memorising facts.
- Practise applying these concepts to explain properties, structures, and behaviours of substances.
- Regularly use scientific language and conventions in your explanations.
- Enhance Your Practical Skills
- Take laboratory work seriously - it accounts for a significant portion of your assessment.
- Practise setting up experiments, handling equipment safely, and following procedures accurately.
- Learn to identify and control variables in experiments.
- Improve Your Data Handling Skills
- Practise organising and presenting data in various forms, including graphs and tables.
- Learn to process data effectively, identifying trends and patterns.
- Develop your ability to interpret data and explain it using relevant scientific concepts.
- Hone Your Analytical and Critical Thinking Skills
- Practise analysing scientific information from various sources.
- Learn to evaluate the quality of scientific evidence and use it to support your arguments.
- Develop the habit of making logical connections between different chemistry concepts.
- Master Scientific Communication
- Practise writing clear, logical responses to chemistry questions.
- Learn to use chemical symbols, formulae, and equations correctly.
- Develop your skill in creating and interpreting chemical diagrams.
- Engage in Regular Study and Review
- Create a consistent study schedule throughout the year.
- Regularly review past topics to maintain your knowledge.
- Use practice questions and past papers to test your understanding.
- Seek Help When Needed
- Don't hesitate to ask your teacher for clarification on difficult concepts.
- Consider forming study groups with classmates to discuss and debate chemistry topics.
- Stay Informed About Real-World Applications
- Keep up with current developments in chemistry and its applications in society.
- This can help you in the 'Science as a Human Endeavour' strand of the course.
- Prepare Effectively for Assessments
- Pay attention to the different assessment types (Science Inquiry, Extended Response, Tests, and Externally Set Task) and prepare accordingly.
- Practise time management in test conditions.
💡 Check out these scientifically proven strategies to improve how you study!
Mistakes to Avoid
To maximise your success in the WACE Chemistry, be aware of and try to avoid these common mistakes:
- Neglecting the Basics
- Don't overlook fundamental concepts from previous years.
- Mistake: Rushing into advanced topics without a solid foundation in basic chemistry principles.
- Memorising Without Understanding
- Avoid rote learning without grasping the underlying concepts.
- Mistake: Memorising chemical equations or processes without understanding why they occur.
- Underestimating Practical Work
- Don't treat lab work as less important than theoretical knowledge.
- Mistake: Not paying attention during practical sessions or rushing through experiments without care.
- Poor Data Handling
- Avoid carelessness in recording, presenting, or interpreting data.
- Mistake: Neglecting to label axes on graphs, using inappropriate scales, or misinterpreting trends.
- Ignoring Safety Procedures
- Never compromise on safety in the lab.
- Mistake: Not wearing appropriate safety gear or disregarding safety instructions.
- Lack of Practice in Problem-Solving
- Don't rely solely on reading and note-taking.
- Mistake: Not doing enough practice questions or avoiding challenging problems.
- Ineffective Time Management
- Avoid last-minute cramming or neglecting certain topics.
- Mistake: Not creating a balanced study schedule that covers all areas of the syllabus.
- Overlooking the Importance of Scientific Communication
- Don't underestimate the need for clear, precise scientific writing.
- Mistake: Using vague language or everyday terms instead of specific scientific terminology.
- Skipping Steps in Calculations
- Avoid rushing through mathematical problems.
- Mistake: Not showing your working or skipping important steps in calculations.
- Misunderstanding Question Requirements
- Don't rush into answering without fully comprehending what's being asked.
- Mistake: Providing irrelevant information or not addressing all parts of a question.
By being aware of these potential pitfalls, you can take proactive steps to avoid them, enhancing your learning and performance in the course.
Link to Past Papers
Why Past Papers are the Best Way to Revise for WACE Chemistry Exam
Using past papers is one of the most effective strategies for preparing for your WACE Chemistry Exam. Here's why:
- Familiarisation with Question Structure
- WACE tends to use consistent question structures across years, which may differ from your textbook or other resources.
- Regular practise with past papers helps you become comfortable with these specific question types, putting you in a strong position for the actual exam.
- Quick Identification of Challenging Areas
- By working through past papers, you can quickly identify which types of questions or content areas you find most difficult.
- This allows you to focus your revision efforts on these challenging areas, maximising the effectiveness of your study time.
- Time Management Practice
- Past papers help you identify which parts of the exam require more time to complete.
- This insight allows you to adjust your time management strategy for the actual exam, ensuring you allocate sufficient time to each section.
- Exam Technique Improvement
- Regular practice with past papers helps refine your exam technique, including how to interpret questions and structure your answers effectively.
- Exposure to Real Exam Conditions
- Using past papers under timed conditions simulates the actual exam experience, helping reduce anxiety and improve performance under pressure.
- Understanding Mark Allocation
- Past papers, along with their marking guidelines, help you understand how marks are allocated for different types of questions.
- This knowledge can guide you in providing sufficiently detailed answers to secure maximum marks.
- Tracking Progress
- By attempting past papers at different stages of your revision, you can track your progress and identify areas of improvement.
- Comprehensive Content Coverage
- WACE exams are designed to cover a wide range of the syllabus. Regular practice with past papers ensures you're revising all key areas of the curriculum.
Caution Note: When reviewing exams from several years ago, be aware that some topics may no longer be part of the current syllabus or may be asked about differently. Always cross-reference with the most recent syllabus and consult with your teacher about any significant changes in exam content or structure over the years.
By incorporating past papers into your revision strategy, you're not just memoriaing content, but actively preparing for the specific challenges of the WACE Chemistry Exam. This approach, combined with thorough understanding of the course material, puts you in an excellent position to succeed in your exam.
Tips for WACE Chemistry Exam: Preparation, Night Before, and Exam Day
General Preparation Tips
- Master the Fundamentals: Ensure you have a solid understanding of basic concepts like atomic structure, bonding, and chemical reactions. These form the foundation of more complex topics.
- Practise Calculations: WACE Chemistry often includes questions on stoichiometry, equilibrium constants, and pH calculations. Regular practice will improve your speed and accuracy.
- Learn Key Definitions: Chemistry exams often test your knowledge of specific terms. Create flashcards for important definitions and review them regularly.
- Understand Chemical Equations: Practice balancing equations and predicting products of reactions. This is a common type of question in WACE Chemistry exams.
- Focus on Practical Knowledge: WACE Chemistry includes questions about laboratory techniques and experimental design. Review common lab procedures and safety protocols.
- Use Mnemonics: Create memory aids for complex concepts or series of steps. For example, "OIL RIG" (Oxidation Is Loss, Reduction Is Gain) for redox reactions.
- Practise Drawing Diagrams: Be prepared to draw and label diagrams of chemical apparatus, molecular structures, or reaction mechanisms.
The Night Before the Exam
- Review Summary Notes: Go through your condensed notes or mind maps, focusing on key concepts and formulas.
- Check Your Equipment: Ensure you have all necessary items: calculator (check it's an approved model), pens, pencils, ruler, and eraser.
- Familiarise Yourself with the Periodic Table: While one will be provided, being familiar with its layout will save time during the exam.
- Light Review of Challenging Topics: Briefly go over any areas you find particularly challenging, but avoid deep studying of new material.
- Prepare Your Outfit: Lay out comfortable clothes and consider layers to adapt to the exam room temperature.
- Set Multiple Alarms: Ensure you'll wake up on time, allowing for a calm morning routine.
- Early Bedtime: Aim for at least 8 hours of sleep to ensure your mind is fresh for the exam.
The Day of the Exam
- Healthy Breakfast: Eat a nutritious meal to fuel your brain. Include proteins and complex carbohydrates for sustained energy.
- Arrive Early: Give yourself plenty of time to reach the exam venue, accounting for potential traffic or public transport delays.
- Last-Minute Review: If it helps calm your nerves, do a quick review of key formulas or concepts, but avoid intensive studying.
- Stay Hydrated: Bring a clear water bottle (if allowed) to keep hydrated during the exam.
- Deep Breathing: If you feel anxious, practice deep breathing exercises to calm your nerves.
- Read Instructions Carefully: Take time to read through all instructions at the start of the exam. Note the marks allocated for each question to guide your time management.
- Start with Confidence: Begin with questions you're most comfortable with to build momentum and confidence.
- Manage Your Time: Keep an eye on the clock. If you're stuck on a question, move on and come back to it if time allows.
- Show Your Work: For calculation questions, always show your working. You may receive partial marks even if the final answer is incorrect.
Remember, the WACE Chemistry exam is designed to test your understanding and application of chemical concepts. Stay calm, trust in your preparation, and approach each question methodically. Good luck!
Conclusion
To excel in WACE Chemistry, focus on understanding the exam format, developing deep conceptual knowledge, and honing your practical skills. Implement effective study strategies and avoid common mistakes.
Don't hesitate to seek help when needed - consider tutoring for personalised support in challenging areas.
Chemistry can be demanding, but with consistent effort and the right approach, including additional guidance when necessary, you can achieve great results. Remember, your success in this course opens doors to understanding the world at a molecular level and potentially to exciting careers in science. Stay curious, work hard, and enjoy your chemistry journey!
