Physical and Chemical Changes

Question 1

What is the definition of a physical change?

Answer 1

A change that can be seen or felt, but that does not involve the break up of the particles during the reaction. During the reaction the form of the matter may change but not its identity.

Question 2

Give three examples of physical changes.

Answer 2

Changes in state.
Conduction.
Dissolving one substance in another

Question 3

List 4 properties of physical changes.

Answer 3

Arrangement of particles may change but the bonds between the atoms will not.
Will always have the same number of molecules/atoms at the end.
Small energy changes.
Easily reversible.

Question 4

What is the definition of a chemical change?

Answer 4

The formation of new substances in a chemical reaction. One type of matter is changed into something different.

Question 5

Give two examples of chemical changes.

Answer 5

Decomposition of Hydrogen peroxide.

The synthesis of water.

Question 6

List 4 properties of chemical changes.

Answer 6

Particles are changed in some way.
High energy changes.
Difficult to reverse.
Mass is conserved but number of particles may change.