1. TEKS 5.5B The student knows that matter has measurable physical properties and those properties determine how matter is classified, changed, and used. The student is expected to: identify the boiling and freezing/melting points of water on the Celsius scale.

2. Boiling point is the temperature at which something becomes a gas.
Water has a boiling point of 100° C.
This means that at 100° C, water changes from a liquid to a gas.

3. Melting point is the temperature at which something becomes a liquid.
Water has a melting point of 0° C.
This means that at 0° C, water changes from a solid to a liquid.

4. Which of the following is the temperature at which ice melts?
0 Kelvin
0o Fahrenheit
0o Celsius
0 Gram

5. Which of the following is the temperature at which ice melts?
A. 0 Kelvin
Incorrect
Kelvin is the measurement unit that includes absolute zero. The temperature would have to be 274 K for ice to melt.

6. Which of the following is the temperature at which ice melts?
B. 0o Fahrenheit
Incorrect
Fahrenheit is the measurement unit that is traditional in the U. S. The temperature would have to be 32o F for ice to melt.

7. Which of the following is the temperature at which ice melts?
D. 0 Gram
Incorrect
A Gram (g) is the measurement unit used to represent mass – not temperature.

8. Which of the following is the temperature at which ice melts?
C. 0o Celsius
Correct
The Celsius scale uses 0o as the melting point.

9. If you are camping at sea level and want to boil water so it will be safe to drink, what temperature will it need to reach?
15 K
100o C
100o F
150 g

10. If you are camping at sea level and want to boil water so it will be safe to drink, what temperature will it need to reach?
A. 15 K
Incorrect
Kelvin is the measurement unit that includes absolute zero. The temperature would have to be 373o K for water to boil.

11. If you are camping at sea level and want to boil water so it will be safe to drink, what temperature will it need to reach?
C. 100o F
Incorrect
Fahrenheit is the measurement unit that is traditional in the U. S. The temperature would have to be 212o F for water to boil.

12. If you are camping at sea level and want to boil water so it will be safe to drink, what temperature will it need to reach?
D. 150 g
Incorrect
A gram is the measurement unit for mass – not temperature.

13. If you are camping at sea level and want to boil water so it will be safe to drink, what temperature will it need to reach?
B. 100o C
Correct
The Celsius scale uses 100o as the boiling point for water.

14. Four students were working together in a lab group
Four students were working together in a lab group. They had to predict the temperature at which pure water would boil. They recorded their predictions in the table below.
Student
Prediction o C 1 75 2 90 3
100 4
125

15. Which student’s prediction was the closest to the boiling point of water?
Prediction o C 1 75 2 90 3
100 4
125
Student 1
Student 2
Student 3
Student 4

16. Which student’s prediction was the closest to the boiling point of water?
C. Student 3
Correct
100o C is the boiling point of water.
Student
Prediction o C 1 75 2 90 3
100 4
125

17. Which student’s prediction was the closest to the boiling point of water?
Incorrect
None of these are the boiling point of water on the Celsius scale.
Student
Prediction o C 1 75 2 90 3
100 4
125

18. Students were doing a lab to find the melting point of ice
Students were doing a lab to find the melting point of ice. Which thermometer would show the temperature in o Celsius at which ice would begin to melt? 1 2 3 4
Thermometer 1
Thermometer 2
Thermometer 3
Thermometer 4

19. Students were doing a lab to find the melting point of ice
Students were doing a lab to find the melting point of ice. Which thermometer would show the temperature in o Celsius at which ice would begin to melt? 1 2 3 4
The correct answer is C
because ice melts above 0o C and
the question asks at what
temperature ice would begin to
melt.

20. because water boils at 100° C.
Students were doing a lab to find the melting point of ice. Which thermometer would show the temperature in o Celsius at which ice would begin to melt? 1 2 3 4
Answer A is incorrect
because water boils at 100° C.

21. because the thermometer reads 50°C.
Students were doing a lab to find the melting point of ice. Which thermometer would show the temperature in o Celsius at which ice would begin to melt? 1 2 3 4
Answer B is incorrect
because the thermometer reads 50°C.

22. because the thermometer reads -5° C.
Students were doing a lab to find the melting point of ice. Which thermometer would show the temperature in o Celsius at which ice would begin to melt? 1 2 3 4
Answer D is incorrect
because the thermometer reads -5° C.