Heat capacity vs Specific Heat capacity

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nathansalce 3e
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Joined: Thu Jul 27, 2017 3:01 am

Heat capacity vs Specific Heat capacity

Postby nathansalce 3e » Fri Jan 19, 2018 11:12 pm

Can somebody explain the difference between heat capacity and specific heat capacity and the significance that they both hold on this chapter. When is one important and when might you consider one or the other?

Naomi Jennings 2H
Posts: 21
Joined: Thu Jul 13, 2017 3:00 am

Re: Heat capacity vs Specific Heat capacity

Postby Naomi Jennings 2H » Fri Jan 19, 2018 11:26 pm

Heat capacity is the amount of energy required to raise the temperature of the system/something by one degree celsius.
Specific heat capacity is the amount of energy required to raise the temperature of one gram of a substance by one degree celsius.
Heat capacity is mostly useful for calorimeters, because problems don't tell you how many grams of different substances a calorimeter has and force you to calculate out how much energy it will take to raise the temperature of a calorimeter (thankfully). The textbook will instead just tell you that in this calorimeter, the temperature will rise one degree with however many kJs of energy added.
Specific heat capacity is probably what we'll be using for the substances that are being combusted in the calorimeter. Because it would obviously release more energy if you burned a stack of paper than if you burned one sheet of paper, it makes sense that the amount of energy released depends on how many grams of something you burn. Therefore, you solve for how much energy is released or absorbed from one gram of a material.
A question might be set up like this:
Energy that flows into calorimeter (surroundings) = - Energy that is released by the system
(Temperature change of the calorimeter)(Heat capacity of calorimeter) = - (Specific heat capacity of system) (grams of substance burned) (temperature change of the system)

Jessica Yang 1J
Posts: 55
Joined: Fri Sep 29, 2017 7:03 am

Re: Heat capacity vs Specific Heat capacity

Postby Jessica Yang 1J » Fri Jan 19, 2018 11:30 pm

Heat Capacity is more generalized and it doesn't matter about the mass of the substance. It is equal to heat supplied/ temperature rise produced. For example, it takes 12 Joules to raise the temperature of water by 2 K. Therefore, the heat capacity of this water is 6 Joules/K.

Specific Heat capacity is more specialized and it matters on the mass of the substance. It applies to all amounts of the substance. For example, the specific heat capacity for liquid water is 4.184 J/g x K for all liquid water.

I think most often you will specific heat capacities for problems because they are defined constants, while heat capacity fluctuates for different circumstances even with the same substances.

Cali Rauk1D
Posts: 51
Joined: Fri Sep 29, 2017 7:03 am

Re: Heat capacity vs Specific Heat capacity

Postby Cali Rauk1D » Thu Jan 25, 2018 12:43 pm

Do the conditions have to be constant for specific heat capacity?

Michael Lee 2I
Posts: 51
Joined: Fri Sep 29, 2017 7:05 am

Re: Heat capacity vs Specific Heat capacity

Postby Michael Lee 2I » Thu Jan 25, 2018 5:14 pm

For specific molar heat capacity you either need gas at constant volume: Cv or at constant pressure Cp.

Jessica Benitez 1K
Posts: 50
Joined: Fri Sep 29, 2017 7:04 am

Re: Heat capacity vs Specific Heat capacity

Postby Jessica Benitez 1K » Fri Jan 26, 2018 10:42 pm

Heat capacity is an extensive property because it depends on the amount of the substance while specific heat capacity is an intensive property.


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