posted by Claudia .
Substance A has a melting point of -10 degree celcius and a boiling point of 57 degree celcius. Sunstance B has a melting point of -67 degree celius and a boiling point of 15 degree celius. Room temperature is 20 degree celcius.
(A) What is the physical state of substance A at room temperature? At 0 degree celcius? At 100 degree celcius?
First, you need to note the correct spelling of celsius.
A mp -10 C, bp 57 C.
B mp -67 C, bp 15 C.
A is a solid below -10 C, melts at -10 and is a liquid between -10 and 57 C, boils at 57 C and becomes a vapor at 57 and above.
Same analysis for B.
I think you can figure it out from that information.