it "sweats" almost like melting plastic on a Bunsen burner, like how small droplets form just before the whole pen melts.
it melts
It indicates that the substance has turned to a liquid.
what the heck are you asking? the melting point is not a substance. it's a temperature in which the substance starts to melt
does the melting point of a substance change over time
It is the boiling point of the substance.
The melting point would also be 21 degrees because the freezing point and melting point of a pure substance is exactly the same.
It is indeed possible for a substance to have a higher melting point than expected. This normally happens when the substance is impure.
it melts
what is the melting point and boiling point of substance
it decreases.
Celsius is a measure of temperature not a substance, and therefore it has no melting point. What is the melting point of what material in Celsius? [You haven't named the substance you want the melting point of/for]
The melting point of a substance varies according to the properties of that substance
It indicates that the substance has turned to a liquid.
what the heck are you asking? the melting point is not a substance. it's a temperature in which the substance starts to melt
does the melting point of a substance change over time
It is the boiling point of the substance.
melting point