Science in Punggol study guide · Article 0005 of 20
Read a table or graph by checking its labels and units, finding the relevant values, and describing the pattern with evidence. Add a science explanation only when the information supports it.
A graph can make a pattern easier to see, but it does not explain the pattern by itself. The question and investigation method help determine what the data means.
On this page: Read the labels and scale · Describe the pattern using values · Keep the conclusion within the evidence · Worked question
Read the labels and scale
The title tells you the subject. Column headings or axis labels identify the quantities. Units show whether values represent minutes, centimetres, degrees Celsius or something else.
Check how much the graph’s scale increases between marked values. Each gap might represent one, five or ten units. Counting grid squares without reading the scale can give an incorrect result.
Also check where the scale begins. An axis does not always begin at zero. Locate the exact time or condition named in the question before reading its value. A number taken from the wrong row or point may be read correctly but still answer the wrong question.
Describe the pattern using values
Use this hypothetical practice dataset for warm water in a cooler room:
- At the start: 50 degrees Celsius.
- After five minutes: 44 degrees Celsius.
- After ten minutes: 40 degrees Celsius.
- After fifteen minutes: 37 degrees Celsius.
“The temperature decreased” describes the overall pattern. “It decreased from 50 to 37 degrees Celsius over fifteen minutes” supports the description with values and a time period.
The temperature drop was six degrees in the first five minutes, four degrees in the next five minutes, and three degrees in the final five minutes. These comparisons use equal time intervals.
Comparing a ten-minute change with a five-minute change without allowing for the different time periods can mislead. Formal rate calculations are enrichment; begin by comparing matching intervals carefully.
Keep the conclusion within the evidence
The dataset shows the recorded temperatures under the stated conditions. It does not show what every cup will do or the exact temperature after an hour. Extending a trend beyond the measured values is a prediction.
Heat transfer from warmer water to cooler surroundings explains the cooling. However, these readings alone cannot show why one cup would cool faster than another. That would require a suitable comparison and details about both setups.
Two quantities changing together do not automatically prove that one caused the other. A graph shows a relationship in the data. Its cause needs to be examined using science knowledge and the investigation method.
Worked question
Question: Using the hypothetical dataset above, during which five-minute interval was the largest temperature drop recorded? Support your answer with the values.
Worked explanation: The largest drop occurred from the start to five minutes. The temperature fell from 50 to 44 degrees Celsius, a drop of six degrees. The next two five-minute drops were four degrees and three degrees, so the first was the largest.
Common mistake: Do not choose the interval ending at the lowest temperature without calculating the change. The question asks for the largest drop, not the lowest reading. Compare the difference between the start and end of each equal interval.
When checking a data answer, separate description from explanation. First state what the values show. Then, if asked, explain the result with a relevant concept. If information is missing, identify what else would be needed.
