States of Matter
What are the 3 states of matter?
Solid, Liquid, Gas
When a solid is heated and changes state to a liquid, this is called?
Melting
What are mixtures?
Mixtures are a combination of two or more substances
What is a solute?
The substance that gets dissolved
What is a hypothesis?
a) A random guess
b) A type of experiment
c) A testable prediction based on observations
d) A question with no answer
C) A testable prediction based on observations
What is matter?
Anything that has a mass and volume
When a liquid is cooled and changes state to a solid, this is called?
Freezing
What are pure substances?
Pure substances are materials that are not combined with anything else
What is a solvent?
the liquid that dissolves other substances.
Which of the following is NOT an observation?
a) The water is 50°C
b) The plant has grown 5 cm
c) I think the plant will grow faster in sunlight
d) The liquid is turning red
C) I think the plant will grow faster in sunlight (This is a prediction, not an observation.)
What three properties can we use to describe the properties of matter?
Shape, Volume, Compressibility
When a liquid is heated and changes state to a gas, this is called?
Vaporisation or Boiling
What is a solution?
mixtures where one substance is dissolved evenly throughout another
A cup of coffee is a solution. Identify the solvent and the solute in this solution.
Solvent: Water – This is the liquid that dissolves other substances.
Solute: Coffee particles (from coffee grounds or instant coffee) – These dissolve in the water to create the coffee solution.
What is the purpose of a control variable in an experiment?
a) To change the results
b) To keep conditions the same so the test is fair
c) To make the experiment more complicated
d) To speed up the investigation
b) To keep conditions the same so the test is fair
What is volume?
the amount of space something takes up
When a gas is cooled and changes state to a liquid, this is called?
Condensation
How could you tell if a mixture is a solution?
What is the difference between a soluble substance and an insoluble substance?
Soluble things mix completely (they dissolve) while insoluble things do not.
Why do scientists repeat experiments?
a) To make them more exciting
b) To check if the results are reliable and accurate
c) To change the results
d) To prove they are always right
b) To check if the results are reliable and accurate
What are the properties of a gas?
Variable shape, variable volume, compressible
Not all substances become a liquid.
When a solid is heated and changes state DIRECTLY to a gas, this is called?
Sublimation
What is a suspension?
A suspension is a mixture where one substance is spread through another, but does not dissolve.
If no more solute dissolves, what is the solution called?
Saturated
Which of the following is an example of a fair test?
a) Changing many variables at once
b) Keeping all variables the same except one
c) Guessing the results before doing the experiment
d) Testing something only once
b) Keeping all variables the same except one