The melting point of the lauric acid on the given graph was about 45 degrees Celsius. The freezing point of the acid on my graph was around 42 degrees Celsius. These two temperatures should be the same. There may be a slight difference in temperature based on the conditions. It would be extremely difficult to heat a solid above its melting point because the heat that enters the solid at it's melting point is used to convert it into a liquid. Although, you can cool a liquid under its freezing point while staying in liquid form by supercooling it (I researched this a little). A liquid can be supercooled because the particles are packed in an odd way that is not characteristic of the liquid. I got the freezing point from my data by looking where the graph sort of leveled out, because when the substance freezes, it's temperature stays relatively the same for a short time.
Kinetic energy is the energy an object (in this case the lauric acid molecules) has when it is in motion. Temperature is a measure of average kinetic energy, so if the temperature increases, so does the kinetic energy, and vice versa. Since temperature doesn't change during melting or freezing, potential energy is the energy that is gained or lost during this process.
Enrichment: The actual melting point of lauric acid is 43.2 degrees Celsius. Our melting point was recorded at 44.5 degrees Celsius. My percent error is calculated to be 3.01%. This may be because the pressure in the chemistry room may have been slightly different than wherever they recorded the actual temperature. (I'd assume they took it at standard pressure, 101.3 kPa, just to be accurate.)
The chemical formula for lauric acid is C12 H24 O2. Lauric acid is used in the lab to find out the molar mass of a substance, using freezing point depression. Freezing point depression is when the freezing point of a liquid is depressed when another compound is added, which means the mix all together will have a lower freezing point. I got all of this from right here.
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