Phase change lab

Question-  What happens to the temperature of water as it goes through a phase change?

Knowledge probe-

1. At what temp does H2O freeze?

2. At what temperature does H2O melt?

3. At what temperature does H2O boil?

4. At what temperature does H2O condense?

5. Which phase of matter are the molecules farthest apart from each other.

 Hypothesis:

Materials:

• Thermometer
• Thermometer clamp
• Hot Plate
• Large Beaker
• Crushed Ice

Procedures:

1. Mix a little water with the crushed ice in the beaker.  The more tightly packed the ice can be, with fewer gaps, the better.
2. Place the beaker above the bunsen burner and position the thermometer so that it will not touch the bottom of the glass.
3. Record the temperature at this point (time 0).  Continue writing down the new temperature each minute.
4. Light the bunsen burner and heat the H2O.
5. Continue recording the temperature at 1 minute time intervals until the water starts to boil. Continue recording your time for another 10 minutes after the water starts to boil.. Note: Do not let the beaker go dry, turn the heat off before the water has all boiled off.
6. Graph your data.  (time on the x-axis/ temperature on the y-axis)

Data analysis

1. What happened to the temperature of the water as the ice melted?

1. What happened to the temperature of the water as it boiled?

Explanation

1. When boiling, where do you think the energy from the burner was going?

1. How does your graph look during the vaporization phase change?

1. How is your graph different when in between phases?

Observation Table:

 Min 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 temp

Graph: