Students know how to solve problems involving heat flow and temperature changes, using known values of specific heat and latent heat of phase change.
Also known as...
CALORIMETRY
You can use a calorimeter to measure the heat quantity of a substance.
Or it can be defined with the infamous equation:
M = Mass
C = Specific Heat Capacity
∆T = Change in Heat Temperature (Final temperature - initial temperature)
A useful constant for C would be the specific heat of water which is 1 cal/grams°C or 4.184 J/grams°C. Ice's specific heat capacity is .5 cal / grams°C and steam's specific heat capacity is 0.4 cal / grams°C.
Water, ice, and steam!
I will demonstrate how to solve for each of the variables (mass, specific heat capacity, and ∆T) in the following video. The step-by-step instructions are supplemented below.
Solving for Q:
A 21.0g sample of water is cooled from 34.0°C to 28.0°C. How many Joules of heat were removed from the water?
In order for calculate the values of ∆T, C, or M, you must use algebra to solve the equation for each of the variables.
I have solved the equations already!
M = Q / C∆T
∆T = Q / MC
C = Q /M∆T
Phase change problems (such as melting from a solid to a liquid) can be solved by using the same formula but by also using the extra formulas:
Q = ∆HVap = 540 cal
Q = ∆HFus = 80 cal
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