9.10 - Answering the Question - The Words Examiners Use & Open-Ended Questions
Why the wording of the question matters
- The command word in an exam question tells you what type of response is needed.
- Using the wrong approach for a command word loses marks even when the chemistry is correct.
Same fact, two different questions
Take one fact: an alkane's boiling point rises as its molecules get longer.
- Describe what happens to the boiling point as the number of carbon atoms increases:
- State what happens: the boiling point increases.
- Explain why the boiling point increases as the number of carbon atoms increases:
- Give the reason: longer molecules have stronger forces of attraction between them, so more energy is needed to separate them.
Writing a "describe" answer to an "explain" question gives no reason and loses the mark.
A typical question
Describe what happens to the boiling point of an alkane as the number of carbon atoms in its molecules increases.
The words examiners use
| Word | What you have to do |
|---|---|
| State, name, identify | Answer briefly with a word, formula, or short phrase. No explanation needed. |
| Describe | Say what happens or what something is like, without giving reasons. |
| Explain | Give the reason - say why something happens or what causes it. |
| Calculate | Work out a number from the data given, including units if requested. |
| Suggest | Apply chemistry knowledge to a new situation. More than one sensible answer may be accepted. |
| Predict | State what you expect to happen based on a pattern or data given. |
| Draw | Produce a diagram, structural formula, or graph. |
| Complete | Fill in part of a table, equation, or diagram that is partly given. |
| Using your knowledge of chemistry, comment on / describe / suggest... | An open-ended question, marked on overall understanding rather than specific points. |
Key distinctions
- Describe vs explain - Describe states what happens; explain states why it happens.
- Predict vs suggest - Predict uses an existing pattern in the given data; suggest applies general principles to a new situation.
Open-ended questions
- Open-ended questions usually begin: "Using your knowledge of chemistry, comment on / describe / suggest..."
- They are judged on the answer as a whole and placed into one of four bands based on overall understanding, rather than scored per individual point.
- There's no single correct answer; various valid chemical arguments can score full marks.
The four bands
- No understanding (0 marks) - No evidence that the relevant chemistry is recognised.
- Limited understanding (1 mark) - At least one relevant, correct statement.
- Reasonable understanding (2 marks) - Statements showing the problem is understood.
- Good understanding (3 marks) - A logically correct response showing clear comprehension, such as applying a relevant principle, relationship, or equation.
How to structure an answer
- Identify the chemistry involved - State the underlying principle or concept.
- State a relevant fact, test, or equation - Provide supporting chemical knowledge.
- Apply it directly to the question - Explain what that chemistry means for the specific scenario given.
Common exam questions
Question 1
What is the difference between a "describe" question and an "explain" question?
Describe asks what happens; explain asks why it happens. An explain answer has to give a reason, so if your answer contains no reason, it is probably only a description.
Question 2
Does National 5 Chemistry publish a list of what each command word means?
No. The general marking principles only say that you must respond to the wording as appropriate. The words that actually introduce chemistry questions can be learned from how the papers use them, but there is no separate published list.
Question 3
A question asks you to "predict" an amount from a table of data. What are you being asked to do?
Read off the pattern already present in the data you are given and extend it, rather than working something out completely from scratch or from general knowledge.
Question 4
A question asks you to "suggest" an experimental test for a situation you have not met before. Does it have one right answer?
Not necessarily. Suggest usually means applying what you know to something new, and more than one sensible answer can be accepted.
Question 5
How many open-ended questions appear on a National 5 Chemistry paper, and how are they worded?
Two, each usually starting "using your knowledge of chemistry, comment on..." or "...describe..." or "...suggest...", followed by a situation or a set of materials.
Question 6
How are the open-ended questions on the National 5 Chemistry paper judged?
On the answer as a whole, placed in one of four bands according to how much understanding of the chemistry it shows: no, limited, reasonable, or good understanding. There is no list of separate points to collect, and a variety of chemistry arguments can be used.
Question 7
What are the three things a good open-ended answer does?
Names the chemistry involved, brings in a relevant fact, relationship, or equation, and applies it to the situation the question describes.
Question 8
Why should you never leave an open-ended question blank?
Because the bands reward the answer overall, so even one relevant, correct statement about the chemistry involved lifts you off the bottom band, while a blank page cannot.