Overview
For Cambridge syllabus 5070, understanding command words is the key to unlocking marks in your Cambridge 5070 Chemistry exams. These words are the examiner's direct instructions, telling you exactly what you need to do to demonstrate your knowledge. In a subject that demands precision, knowing the difference between 'describe' and 'explain' can be the difference between a pass and a distinction. For a general overview, you can read our guide to [Cambridge command words explained](/blog/cambridge-command-words-explained), but this article will focus specifically on what they mean for 5070 Chemistry.
Foundational Command Words: State, Define, and Describe
For Cambridge syllabus 5070, these are the building blocks of your exam paper, often appearing in lower-tariff questions. They test your ability to recall information accurately and concisely. State requires a short, factual answer with no explanation. For example, 'State the test for chlorine gas' needs the answer 'It bleaches damp litmus paper', and nothing more. Define asks for a formal, syllabus-perfect definition of a scientific term; you must use precise chemical language, as if writing a textbook. Describe requires you to give a step-by-step account of what happens in a process or what you would observe in a reaction. For observations, focus on colours, physical states (precipitates, gases), and smells.
Calculation and Data Handling: Calculate and Suggest
For Cambridge syllabus 5070, chemistry is a quantitative science, and these command words test your numerical and analytical skills. When you see Calculate, you must produce a numerical answer, and you will only get full marks if you show all your working clearly and include the correct units. This is crucial for topics like moles, stoichiometry, and rates of reaction. The word Suggest invites you to apply your chemical knowledge to a new or unfamiliar context. You need to propose a scientifically plausible reason or hypothesis based on the information provided. There may be several correct answers, but your suggestion must be logical and well-reasoned, not a random guess.
Explanatory Command Words: Explain and Predict
For Cambridge syllabus 5070, this is where you move from simple recall to demonstrating deeper understanding. Explain is one of the most common and important command words in 5070 Chemistry. It requires you to provide reasons *why* something occurs, linking cause and effect using scientific principles. A good explanation will refer to concepts like bonding, structure, particles, and energy changes. For instance, explaining the trend in reactivity down Group 1 involves discussing atomic radius, shielding, and the ease of losing the valence electron. Predict asks you to use your knowledge of patterns and trends (like those in the Periodic Table) to determine a likely outcome or property. You are making a logical forecast based on the data and principles you have learned.
Higher-Order Skills: Discuss, Evaluate, and Justify
For Cambridge syllabus 5070, these command words are reserved for the most challenging, high-tariff questions that separate the top candidates. Discuss, Evaluate, and Assess all require a balanced, two-sided argument. You must explore both the positive and negative aspects, or the arguments for and against a particular topic (e.g., the use of a certain plastic or industrial process). Simply listing points is not enough; you must develop these points and, crucially, finish with a supported conclusion or judgement that weighs up the evidence you have presented. Justify requires you to provide evidence and reasoning to support a given statement or conclusion. You are essentially defending a position using your chemical knowledge.
Command Words in the Practical Context
For Cambridge syllabus 5070, your practical paper (Alternative to Practical or the Practical Test) relies heavily on a specific set of command words. Describe is paramount, used for detailing the observations you would make during an experiment. Precision is vital: 'a white precipitate was formed' is a much better answer than 'it turned cloudy'. Identify asks you to name a substance (an ion or a gas, for example) based on the results of qualitative analysis tests. You may also be asked to Explain the choice of a particular piece of apparatus or procedural step. Success in this paper comes from linking observations to underlying chemical identities and reactions, a core skill detailed in the [5070 Chemistry syllabus](/subjects/5070).
Frequently asked questions
This section covers Frequently asked questions — ranked by what Cambridge examiners return to most often in past papers.
What's the difference between 'Describe' and 'Explain' in a reaction context?
'Describe' asks for the observable phenomena – what you would see, hear, or smell. For example, "A vigorous effervescence was seen and a colourless gas was produced." 'Explain' asks for the underlying chemical reason for those observations. For example, "The hydrochloric acid reacts with the magnesium carbonate to produce carbon dioxide gas."
How do I get top marks for an 'Evaluate' question?
To reach the highest marks, you must present a balanced argument, considering both the advantages and disadvantages with specific chemical detail. Most importantly, you must end with a concluding paragraph that makes a clear, supported judgement, summarising which side of the argument is stronger and why. A simple list isn't sufficient.
Do I always need to write balanced chemical equations?
Yes, almost always. In 5070 Chemistry, writing a full, balanced chemical equation with correct state symbols is a fundamental skill. If a question describes a chemical reaction, assume an equation is required for full marks unless it explicitly states otherwise. If you want to see how this is applied in practice, you can mark a paper with us.