Name _______KEY___________________________________ Date _________ Period ______
Heating Curve
1.
At which leg is the solid being warmed? The liquid? The vapor?
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2.
What is the substance’s normal boiling point? Which leg on the curve is this? Explain.
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3.
The substance will crystallize at 0 °C. It occurs at the same temperature as
melting, which occurs during leg b.
If heat is added at a constant rate, what other unit could be used on the x-axis?
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8.
The particles are moving apart during leg d. The kinetic energy is not changing,
as the temperature is remaining constant.
At what temperature would this substance crystallize? Explain how you know.
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7.
At point c, kinetic energy is being added to the system. The positive slope
indicates a change in temperature, which is the measure of kinetic energy.
What is happening to the distance between the particles and kinetic energy during leg b?
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6.
The substance’s normal melting point is 0 °C. This is point b, between the
heating of the solid and liquid.
Which energy (kinetic/potential) is added during leg c? How does the graph show this?
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5.
The substance’s normal boiling point is 100 °C. This is point d, between the
heating of the liquid and gas.
What is the substance’s normal melting point? Which leg on the curve is this? Explain.
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4.
The solid is being warmed at a, the liquid is being warmed at c, and the gas is
being warmed at e.
If heat is supplied at a constant rate, time can be used on the x-axis.
Is the heat of vaporization more or less than the heat of fusion? Explain how you know.
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The heat of vaporization is higher because leg d (900-3100 kJ) is much longer
than leg b (100-500 kJ).