Frosh PhySci - Freezing quiz

Question 0

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What causes a liquid to freeze?

Answer 0

Cooling particles lose energy and are overcome by the force of attraction between them to bond closer together.

Question 1

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What is freezing?

Answer 1

Process of liquid changing to a solid.

Question 2

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The temperature at which a substance freezes is called its __________

Answer 2

Freezing point

Question 3

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The freezing point of pure water is ___________ degrees Celsius

Answer 3

Zero - 0

Question 4

Which of these substances has the highest  freezing point?  
a- salt water
b- carbon
c- sodium
d- iron

Answer 4

a- salt water The only liquid. All the others are solid at room temp and therefore have higher “freezing” points.

Question 5

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T/F A liquid freezes because its particles lose energy

Answer 5

True

Question 6

Room temperature is considered to be 20 degrees Celsius. Give an original example of a substance with a freezing point lower than 20C.

Answer 6

Anything that is liquid or gas at room temperature.

Water, milk, coffee, air, oxygen, etc

Question 7

F -

T/F Freezing point is a chemical property of matter

Answer 7

False Only a change of state

Question 8

Explain why road crews put salt on icy roads

Answer 8

To melt the ice. Adding the salt lowers the freezing point of the water.