Phases of Acetone and Diphenyl at room temp

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The discussion centers on the physical properties of acetone and diphenyl, particularly their melting and boiling points. Acetone has a melting point of -95°C and a boiling point of 56°C, leading to confusion about its state at room temperature (20°C). The key point is that at 20°C, acetone is indeed in its liquid state because it has already transitioned from solid to liquid at temperatures above -95°C. The argument highlights that just because a substance's melting point is below room temperature does not mean it is solid; rather, it indicates that it has already melted. The comparison with water illustrates that substances can exist as liquids at temperatures above their melting points, reinforcing the understanding of phase transitions. The discussion emphasizes the importance of recognizing the normal phase of a substance based on its temperature relative to its melting and boiling points.
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I was reviewing a chart of Physical properties of pure substances (20 °C)

Acetone has a melting point of -95°C and boiling point of 56°C so you'd assume it's solid (but obvioulsy it's liquid). In addition, Diphenyl has a melting point of 70°C and boiling point of 255°C so you'd assume it's liquid (but it's solid).

What characteristics am I overlooking?
 
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Acetone melts at -95 degrees. Room temperature is 20 degrees. Why would this be a solid?
 
20°C is is greater than -95°C (melting ) so acetone would not have melted and is less than 56°C (boiling) so acetone would not have evaporated; I'm assuming the normal phase of acetone is liquid and you don't merely assume because something hasn't melted or boiled that it is solid? Is my presumption correct?

I honestly don't see what I'm missing.
 
20°C is more than -95°C, so the acetone will melt. See, water has melting point of 0°C, but you "drink" water, don't you? According to your argument, we must be eating ice.

Acetone was melted long ago (-95°C is not the temperature to come across easily), so we see it in its melted, liquid form. Just heat it past its boiling point, it will convert into vapour form.
 
biochem850 said:
20°C is is greater than -95°C (melting ) so acetone would not have melted and is less than 56°C (boiling) so acetone would not have evaporated; I'm assuming the normal phase of acetone is liquid and you don't merely assume because something hasn't melted or boiled that it is solid? Is my presumption correct?

I honestly don't see what I'm missing.

melting is the transition from solid to liquid.

-95 is when solid acetone transforms to liquid acetone. you then raise the temperature to 20 degrees, which is below 56.
 
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