A winters day

A winters day

Pencil and paper
Overview
Connecting to the Curriculum
Marking Student Responses
Working with Students
Further Resources
This task is about recognising physical and chemical changes.
A physical change is reversible and no new substance is made; a chemical change is not reversible and a new substance is made.
 
a)
When a candle burns, a physical and a chemical change occurs.
 
  i)
 
ii)
What is the physical change? ______________________________

What is the chemical change? ______________________________
 
b)
Read the paragraph below, then complete the table by:
  1. identifying three other changes mentioned in the paragraph and;
  2. circling whether each of the six changes is physical or chemical
 
Amanda sat beside the roaring fire watching the wood burn. She slowly stirred her coffee to dissolve the sugar. The cake cooking in the oven made steam condense on the window.
Amanda looked outside; the snow had started melting. Suddenly, she heard a loud noise. Was it dynamite exploding?
No, it was much worse! Her car's petrol tank burst into flames.  
 

Change (mentioned in the paragraph)

Physical or chemical change
Wood burning a)         physical / chemical
Steam condensing b)         physical / chemical
Dynamite exploding c)         physical / chemical
d) g)         physical / chemical
e) h)         physical / chemical
f) i)          physical / chemical
Level:
5
Curriculum info: 
Science, Investigating in science, Material World
Keywords: 
changes, chemical change, physical changes
Description of task: 
Students explain the terms physical and chemical change. Then they read a passage of text and identify the six changes that have occurred and state if each change is a physical or a chemical change.
Curriculum Links: 
Science capabilities
The capabilities focus is brought about by the conversations you have and the questions you ask.
 
Capability: Gather and Use evidence
This resource provides opportunities to discuss using criteria to make a decision to answer a question.
Science capabilities: 
Gather and interpret data, Use evidence
Answers/responses: 
   Y10 (05/1999)
a) i)
ii)		 The wax melting.
The burning of the candle (wick).		 moderate
moderate
b) a)
b)
c)

d)
to
i)
 

 Chemical
Physical
Chemical

Any 3 of:

  • sugar dissolving – physical
  • cake cooking – chemical
  • snow melting – physical
  • petrol (tank) exploding/burning – chemical
 3 correct – difficult

2 correct – difficult

 

3 marks – difficult

2 marks – easy

1 mark – very easy
Diagnostic and formative information: 
  Analysis of responses
b) a)   29% got this change correct.
b)   44% got this change correct.
c)   59% got this change correct.