Page 8 - Big Ideas Year 10 sciPAD 2025
P. 8

PHOTOCOPYING PROHIBITED
© Silverback Academic Media
8 SCIPAD - BIG IDEAS - BOOK 2
NATURE OF THE ATOM
(e) An explosion is a

change because 



Chemical Change vs. Physical Change
Scientists study two types of changes that occur in substances: chemical changes and physical
changes.
Chemical changes occur when a new substance is formed. When a chemical change occurs
there are certain signs to look for. We usually look to see if two or more of these changes have
occurred to say that a chemical change has happened, and a new substance has been made.
A physical change is not a permanent change. You can easily get back the material that you
started with. State changes (e.g. a liquid changing into a solid) are common examples of physical
changes.
Signs of a chemical change
•
A gas has been given off.
•
There is a colour change.
•
There is a different smell.
•
There is heat given out or absorbed.
•
The change cannot easily be reversed.
Signs of a physical change
•
The substance changes state (liquid to
gas, or solid to liquid, etc.).
•
The change can be easily reversed.
•
No new substances are formed.
•
The mass is the same at the end of the
change.
1. Outline whether the following pictures show a chemical change or a physical change.
Justify your answer.
(a) Frying an egg is a

change because 



(b) Burning a match is a

change because 



(c) Baking bread is a

change because 



(d) An ice cube melting is a

change because 



(f) Making a coffee is a

change because 



Unchecked Sample Pages
For Review Purposes Only - Photocopying Prohibited
www.scipad.co.nz























   6   7   8   9   10