Gases
Properties of Water
Evaporation and Condensation
Solutions
100
How can you describe gas particles?
Word bank:
Choose one: close together | far apart from each other | closely packed but further apart
Choose one: vibrate | slide past one another | move freely
"Far apart from each other" and "move freely"
100
What do we call water when it's in a solid state?
100
What do we call water when it turns into a gas?
Water vapour.
100
What is a solution and how is it defined?
A solution is a mixture where one or more substances are dissolved in another substance.
200
Which gases make up the majority of air?
Nitrogen, oxygen, carbon dioxide and water vapour.
200
What happens to solid water when heat is applied to it?
It changes state to liquid. OR It melts.
200
What is condensation?
Condensation occurs when water vapour or other gases cool enough to change into a liquid.
200
Define soluble and insoluble solids in relation to solutions.
Soluble solids can dissolve in a liquid, while insoluble solids cannot dissolve in a liquid.
300
Which substances can cause air pollution? Say 2.
Smoke, dust and gases from factories and exhausts.
300
At what temperature does pure water freeze?
0ºC
300
What is the outcome of condensation?
Liquid water.
300
How can dissolved chemicals contribute to water pollution?
Dissolved chemicals, such as acids, chemical fertilizers, and pesticides, can pollute rivers and lakes.
400
Name some substances that are gases. Say 2.
air, helium, carbon dioxide, hydrogen, …
400
What happens to liquid water when heat is applied to it?
It changes state to gas. OR It evaporates.
400
What makes water evaporate from rivers, lakes and seas?
400
Why can most mixtures be separated?
Most mixtures can be separated because the particles of the substances are not chemically joined together.
500
What is the atmosphere?
A layer of gases that surrounds the planet.
500
How does heating affect the volume of water?
Heating makes water change states and expand, while cooling makes it contract.
500
Why is the water cycle important to us?
The water cycle is important to us because it keeps moving water between the air and the Earth's surface so that the Earth doesn't dry up. It allows us to use the same water over and over again.
500
Describe the reversible process used to separate a solution, and provide an example.
The reversible process used to separate a solution is evaporation. For example, when saltwater evaporates, leaving behind solid salt crystals, it is a reversible process because the water can be recovered by condensation.