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Valeria Viera 1B
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Postby Valeria Viera 1B » Sun Feb 10, 2019 11:10 pm

I’ve seen this equation written as q=nCdeltaT and q=mCdeltaT
Should we use moles or grams for this equation on the test?

Celeste 1I
Posts: 44
Joined: Fri Sep 28, 2018 12:18 am

Re: q=mCdeltaT

Postby Celeste 1I » Sun Feb 10, 2019 11:12 pm

Use the one that is easiest to use, I'm assuming. If they give you grams then use m and if they give you mols use n. Just make sure to then use the corresponding C. Write out your units to ensure you're getting the right answer and everything cancels out.

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Re: q=mCdeltaT

Postby mahika_nayak_3L » Sun Feb 10, 2019 11:19 pm

Use either m or n depending on the units of the specific heat, C, that is given to you. That way your units can be consistent with one another and cancel out to give you a q value in terms of Joules.

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Re: q=mCdeltaT

Postby MichelleRamirez_2F » Tue Feb 12, 2019 2:29 pm

If you are given moles then use n and molar heat capacity, nad if you are given mass (g) then use m and specific heat capacity of the substance.

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Re: q=mCdeltaT

Postby IsabelLight2H » Tue Feb 12, 2019 3:32 pm

I would just make sure your final answer is in the units they ask for! Don't give moles if they ask for mass and vice versa!

Xingzheng Sun 2K
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Re: q=mCdeltaT

Postby Xingzheng Sun 2K » Wed Feb 20, 2019 11:33 pm

mC represents the specific heat capacity is measured in per unit of mass; nC means the specific heat capacity is measured per mole.

Hadji Yono-Cruz 2L
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Re: q=mCdeltaT

Postby Hadji Yono-Cruz 2L » Sun Feb 24, 2019 1:00 am

Use whichever the question is asking for, but if you are not given the molar heat capacity then convert the moles into grams and use specific heat capacity.

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Re: q=mCdeltaT

Postby MichaelMoreno2G » Sun Feb 24, 2019 8:38 am

What would be the final units for the equations? In other words, if we used moles, what would our final units be, and if we used m, what would our final units be? I get confused with the two.

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Re: q=mCdeltaT

Postby varunhariharan » Mon Feb 25, 2019 9:58 am

The units either way should be in Joules because the moles/grams unit will be cancelled in the equation by the specific heat capacity.

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Re: q=mCdeltaT

Postby yuetao4k » Fri Mar 15, 2019 6:31 pm

It depends on what units are given in the problem. Use whichever is simplest.

Nghi Nguyen 2L
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Re: q=mCdeltaT

Postby Nghi Nguyen 2L » Fri Mar 15, 2019 9:22 pm

i just look at the units for the specific heat, they should tell you to use grams or moles

Heidi Ibarra Castillo 1D
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Re: q=mCdeltaT

Postby Heidi Ibarra Castillo 1D » Sat Mar 16, 2019 10:31 pm

I assume if they give you grams you use m, if moles then youd use n.

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Joined: Wed Sep 18, 2019 12:20 am

Re: q=mCdeltaT

Postby 805097738 » Mon Jan 27, 2020 12:38 pm

if the equation uses the g variable then use grams. If it uses the m variable which is usually represented by n, use number of moles.

Robin Cadd 1D
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Re: q=mCdeltaT

Postby Robin Cadd 1D » Mon Jan 27, 2020 2:01 pm

Either works! Choose whichever one is most convenient for the problem.

Keerthana Sivathasan 2E
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Joined: Wed Sep 18, 2019 12:22 am

Re: q=mCdeltaT

Postby Keerthana Sivathasan 2E » Mon Jan 27, 2020 2:47 pm

Q=mcdeltaT can be used for any solid, liquid or gas, but specifically for gases, if you have constant volume, you can use the equation, nCvdeltaT, or constant pressure, nCpdeltaT. Cv and Cp both are called molar heat capacities.

Verity Lai 2K
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Joined: Sat Aug 24, 2019 12:18 am

Re: q=mCdeltaT

Postby Verity Lai 2K » Tue Jan 28, 2020 11:54 am

If they give you the moles, use q=nCdeltaT, if they give you grams, use q=mCdeltaT. It depends on the information given.

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