But I know, sometimes you just want to memorize a mathematical formula and plug numbers in. If that's what you're looking for, then this is just for you. Heat capacity problems can pretty much all be solved using the formula:
(Energy transferred) = (Heat capacity) x (Amount of substance) x [(Final temperature) - (Initial temperature)]
Or, if we want to make that shorter:
E = (Cp) x (g) x (Tfinal - Tinitial)
Let's plug in information from 2 different problems:1. A 250.0g sample of water (Cp = 1 calorie/(g)(°C)) is heated from 14.3°C to 27.4°C. How many calories of heat energy have been transferred?
Plugging in to the formula:
E = (1 calorie/(g)(°C)) (250.0g) (27.4°C - 14.3°C) = 3275calories
2. A 400.0g sample of water is initially at 16.8°C. If 5000 calories of energy is added to the water, what is the final temperature?
Plugging in again:
5000 calories = (1 calorie/(g)(°C)) (400.0g) (Tfinal - 16.8°C)
Same thing, but now we have to do a little algebra to solve for Tfinal, and we get a final temperature of 29.3°C.If you prefer a more descriptive solution to heat capacity problems, take a look at http://scienceofcooking100.blogspot.com/2015/11/heat-capacity.html
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