Year 7 Science · Unit 4 · Lesson 6

Running an Investigation

Master Worksheet

Name
Date
Class

Learning Goals

Read the line graph

This line graph shows the temperature of a cup of hot cordial measured every 5 minutes as it cooled on a bench. Use it to answer the questions below.

Line graph of cordial temperature in degrees Celsius against time in minutes, showing temperature falling from 80 degrees at 0 minutes to 35 degrees at 25 minutes 20 40 60 80 100 0 5 10 15 20 25 Time (minutes) Temperature (°C)

(a) What was the temperature at 0 minutes, and at 10 minutes?

(b) Describe the trend, and explain what is happening to the cordial.

Plan an investigation

Scenario

A classmate claims that "the warmer the water, the faster a teaspoon of sugar dissolves in it." This is a claim that science can test. Your job is to plan a fair, controlled investigation, then design a results table ready to fill in. Remember a fair test changes only one thing at a time and keeps everything else the same.

(a) Name the independent variable, the dependent variable, and two controlled variables for this investigation.

Challenge 4 marks

(b) Design a blank results table for this investigation. Give each column a clear heading with its correct unit, and include enough rows for at least four different water temperatures.

Challenge 3 marks
Column 1 heading and unitColumn 2 heading and unit

(c) Predict the trend you expect on a line graph of your results, then explain how you would use the graph to write a conclusion that answers the question.

Challenge 3 marks

(d) Evaluate this statement: "Measuring the dissolving time only once at each temperature is enough to be sure of the trend." Do you agree? Justify your answer.

Challenge 4 marks

Wrap Up

In one sentence, what was the main idea of this lesson?