Posted by Skrillex on .
How much heat is required to warm 229 g of ice from -45.3°C to 0.0°C, melt the ice, warm the water from 0.0°C to 100.0°C, boil the water, and heat the steam to 173.0°C?
There are two formulas you use.
If you are within the same phase, use
q = mass x specific heat in that phase x (Tfinal-Tinitial).
Example. q for 25g H2O from 5 C to 95 C is
q = mass x specific heat x (95-5) = ?
The other is at a phase change; i.e., ice melting or water boiling to steam.
q = mass x heat fusion for melting.
q = mass x heat vaporization for liquid water turning to steam.
The easiest way to do these problems is in pieces.
ice from -45.3 to zero C.
raise T from zero C to 100 C
raise T of steam from 100 to 173.0C.
Then add all of the q values together to find the total Q.