Phase Changes Lab
Introduction: We haven’t explicitly talked about what a phase change is, but I’m guessing you’ve heard
the term used previously. A phase change is what happens as something changes from one state (solid,
liquid, gas, plasma) to another. We’re going to explore what happens as something changes from one
phase to another, and explore how temperature changes during a phase change. You’ll need to do the
following:
Objective: Our objective is to investigate what happens to the temperature of ice water as it heats up.
We will branch this into understanding what role “Q” plays in this process.
Submission Expectations: What you give back to me should consist of the following: Analyzing
Questions, Temperature vs. time table (table with your temperature vs. time values each 30 seconds),
and Temperature vs. time graph. You can just send a screenshot of your graph.
Procedures:





Get equal amounts of water in two different cups. One cup should have COLD water, the other
should have room temperature water. Be sure there’s not so much in one cup that when you
combine the two into one cup you won’t have any water spilling out of the cup.
Get a sufficient amount of ice in the cold water cup that the ice stops melting and remains
suspended in the water.
Put the ice into the cold cup, let the ice and water mix. Take the temperature of the water. If all
the ice melts, be sure to put MORE ice in it. We want a stable ice/water mixture. Take the
temperature of the ice/water mixture. You’ll start a timer now.
Mix the room-temperature water in with the ice water. Keep the thermometer in the mixture.
Measure the temperature every 30 seconds. You can stop 5 minutes AFTER all your ice has
melted.
Make a temperature vs. time graph to mark how the temperature changes over time. Do this in
Excel or Google Sheets.
Analysis Questions to answer:
Analyzing questions:
1.
2.
3.
4.
5.
6.
7.
8.
Talk about the different portions of the graph. When is it going up? Is it ever flat?
Why do you think it’s going up or flat? What is happening during this time of the experiment?
When the temperature is changing, is it relatively flat?
What is happening to the molecules of the ice as it heats up?
What is happening to the molecules of the water as the ice melts?
At this rate, make a prediction about when you think the ice will be all melted in your time table.
What direction does the heat transfer? Aka which cup of water transfers the heat to the other?
Is it theoretically possible that some heat transfers from the cold cup to the warm cup? Speak
about this in terms of the definition of temperature.