I need help to know if Ethanol has a melting point of -115c and a boiling point of 78c what state will it be at -20c?

2 Answers
Mar 7, 2018

Liquid

Explanation:

The best way to deal with something like this is to use the familiar.
Water has a melting point at 0C and a boiling point at 100C. Below mp it is solid ice...above melting point it is liquid water (up to 100C), and above 100C it is steam (gas).

Ethanol.....solid......-115C....liquid.......78C.....gas. At -20c, it will be liquid, since -20 is warmer than -115C and colder than 78C

Mar 7, 2018

It will be a liquid.

Explanation:

If ethanol #(C_2H_5OH)# has a melting point of #-115^@"C"#, then it will turn from solid to liquid at that temperature, and will be a liquid if the temperature is greater than #-115^@"C"#.

Ethanol also has a boiling point of #78^@"C"#, and so it will turn from liquid to gas at that temperature, and if it is less than that temperature, it will be a liquid.

We got the ethanol at #-20^@"C"#.

Note that:

#-115^@"C"<-20^@"C"<78^@"C"#

#=>"melting point"<-20^@"C"<"boiling point"#

So, the ethanol will exist as in its liquid form.