Name ______
What’s the Temperature of Boiling & Melting Water
Equipment: hot plate 250mL beaker watch glass (the thing the steel wool was on)
Thermometer tongs w/ black ends
Procedures:
1) Fill the 250ml beaker to the 100mL line exactly.
2) Place the beaker on the hot plate with the watch glass on top of it.
3) Turn the hot plate on medium-hot & wait for the water to start to boil.
4) Look at the volume of water in the beaker as it gets hotter. Does it stay at the 100mL line, go above or below it? Why do you think this happens?
5) Once the water is at a rolling boil, use the tongs to remove the watch glass & set it on the labtop.
6) Place a thermometer in the beaker so that it is suspended in the middle of the water. Once it stabilizes, record the temperature of the water in the table below.
7) Remove the thermometer & replace the watch glass & leave the heat on.
8) Find the beaker/bucket of ice water, mix it around then carefully suspend a thermometer in the ice water so that it is suspended in the middle of the ice water. Wait for the temperature to stabilize. In the table below, record the temperature of the mixture.
9) Repeat steps 5-8 until you have 3 temperature recordings. Turn off the heat after your last boiling temperature recording.
10) Clean up & return supplies to the appropriate place.
Data Table
Temp 1 / Temp 2 / Temp 3Boiling
Melting
Post lab questions
1) Summarize what you saw in terms of the temperature of boiling & melting water over time.
2) Thermal energy was still being added to these containers over the course of time. Explain why you saw what you did in regard to the temperature.
3) Find your Phase Change SE document from last month. Compare what you saw in the lab to what you saw in the gizmo. Revisit the gizmo if need be.