Guide
Working Scientifically
Every HSC science paper examines two things at once: the content of the modules, and the seven skills below. Most students revise only the first. The skills questions — design, error, data — are where a Band 6 is quietly won, because they repeat across every module and every year.
1.Questioning and predicting
Framing a testable question or hypothesis about a relationship between variables.
How it is examined
- “Formulate a hypothesis for this investigation” — name the independent and dependent variable and the expected direction of the relationship.
- Spotting that a given question is NOT testable, and fixing it.
2.Planning investigations
Designing a valid, reliable method: what you change, measure, and hold constant.
How it is examined
- “Identify a variable that must be controlled and explain why” — the why is what earns the mark.
- Choosing equipment for the precision the question demands (burette vs measuring cylinder).
- Validity = the method tests what it claims to test. Reliability = repeats agree. Accuracy = close to the true value. Markers expect the right word for the right idea — they are not interchangeable.
3.Conducting investigations
Carrying out the method safely and recording appropriate data.
How it is examined
- Risk-assessment rows: hazard → harm → precaution, specific to THIS experiment (“wear safety glasses” alone rarely scores).
- “Why is the flask rinsed with distilled water / why is the burette rinsed with the solution it will hold?” — procedure-reason pairs.
4.Processing data and information
Turning raw results into usable form: tables, graphs, averages, outliers.
How it is examined
- Tables with units in the HEADER, consistent decimal places, concordant titres averaged (outliers excluded WITH a reason).
- Graphing: labelled axes with units, sensible scale, line of best fit — and reading a gradient or intercept off it, showing the rise-over-run working.
5.Analysing data and information
Finding the trend, relationship or error story inside the processed data.
How it is examined
- “Describe the relationship shown” — name the variables, the direction, and whether it is linear/proportional, citing values from the data.
- Error analysis: systematic (shifts every reading one way; improves with calibration) vs random (scatter; improves with repeats). Naming which one the scenario shows is a classic discriminator.
- Percentage error and whether a result is accurate, reliable, valid — judged separately.
6.Problem solving
Applying scientific understanding to a new or imperfect situation.
How it is examined
- “The student's value is 12% below the accepted value — propose a cause”: the cause must be physically capable of producing an error in THAT direction.
- Redesign questions: change ONE named feature of the method and justify how it fixes the identified flaw.
7.Communicating
Presenting scientific ideas precisely: correct terms, symbols, units and structure.
How it is examined
- Correct scientific vocabulary throughout — the difference between “amount”, “mass” and “concentration” matters.
- Equations balanced with states; units carried through working; significant figures matched to the data given.
Directive verbs
The verb that opens a question — explain, assess, calculate — tells you exactly what the marker needs. In any practice question on Particle, tap the underlined verb to see what it demands.
Practise now →