How can I graph changes of states of matter?

1 Answer
Jun 20, 2014

If you are adding heat to a sample at a constant rate, you plot the temperature against time.

Temperature is the vertical axis. Time is the horizontal axis. You get a graph like the diagram below.

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If you heat the solid, it gradually warms up. You get the blue line in the graph above.

At some point, the solid will melt. You reach a plateau where the temperature remains constant as long as both solid and liquid are present. The heat energy is used to convert the solid into a liquid, so the temperature does not change.

Once the solid has melted, the added heat goes into warming up the liquid. You get the green line in the graph.

At another point, the liquid will boil. You reach a second plateau where the temperature remains constant as long as both liquid and gas are present. The heat energy is used to convert the liquid into a gas. Again, the temperature does not change.

Once the liquid has disappeared, the added heat goes into warming up the gas. You get the red line in the graph.

Hope this helps.