Suppose that you are taking a melting point and the compound ...

[shenderson6]

Suppose that you are taking a melting point and the compound disappears: What happened?
  Why did it do this? What should you do?

Question 2

You think that you have isolated aspirin (acetylsalicylic acid) in the lab. It melts at 7577C.
  Since you dont totally trust your own laboratory techniques, you want to prove to yourself
  that you have aspirin. Using only melting-point techniques, explain how you can prove that
  you actually have aspirin. (Assume the stockroom is able to supply you with any compound
  you need.)

[anyusername12131]

Answer to Question 1

The compound probably sublimed. You should take the melting point in a sealed melting
point capillary using a Mel-Temp melting-point apparatus.

Answer to Question 2

Obtain a sample of pure acetylsalicylic acid and mix it to a homogenous mixture with your isolated aspirin. Take a melting point of the mixture; if the melting point is about 75-77, the sample you isolated is most likely aspirin