5-4 What is boiling point?
SWBAT: Identify the boiling point of a liquid. Differentiate between boiling and evaporation.
boiling point: temperature at which a liquid changes to a gas
evaporation: change from a liquid to a gas
• When a liquid reaches its boiling point, it begins to change into a gas.
• When a liquid is allowed to stand uncovered at room temperature, it evaporates.
• Evaporation is the change from a liquid to a gas at the surface of the liquid.
1. Define: What is boiling point?
2. Analyze: Which liquid below has the highest boiling point?
3. Define: What is evaporation?
Checking Concepts:
1. When water __________________, it changes to steam.
2. The temperature at which water changes to steam is its __________________.
3. The boiling point of water is __________________ degrees Celsius.
4. When a liquid reaches its boiling point, it begins to change to a __________________.
5. An uncovered liquid changes to a gas at room temperature by the process of __________________.
6. Evaporation occurs only at the __________________ of a liquid.
Thinking Critically
7. Compare: In your own words, explain the difference between boiling and evaporation.
8. Hypothesize: Why is it possible to get a more serious burn from steam than from boiling water?
9. Explain: As water is heated, what evidence is there that a gas is forming?
10. Infer: When does the temperature of boiling water rise above 100 degrees Celsius?
boiling point: temperature at which a liquid changes to a gas
evaporation: change from a liquid to a gas
• When a liquid reaches its boiling point, it begins to change into a gas.
• When a liquid is allowed to stand uncovered at room temperature, it evaporates.
• Evaporation is the change from a liquid to a gas at the surface of the liquid.
1. Define: What is boiling point?
2. Analyze: Which liquid below has the highest boiling point?
3. Define: What is evaporation?
Checking Concepts:
1. When water __________________, it changes to steam.
2. The temperature at which water changes to steam is its __________________.
3. The boiling point of water is __________________ degrees Celsius.
4. When a liquid reaches its boiling point, it begins to change to a __________________.
5. An uncovered liquid changes to a gas at room temperature by the process of __________________.
6. Evaporation occurs only at the __________________ of a liquid.
Thinking Critically
7. Compare: In your own words, explain the difference between boiling and evaporation.
8. Hypothesize: Why is it possible to get a more serious burn from steam than from boiling water?
9. Explain: As water is heated, what evidence is there that a gas is forming?
10. Infer: When does the temperature of boiling water rise above 100 degrees Celsius?