equations for q

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Jennifer Lathrop 1F
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Joined: Sat Dec 02, 2017 3:00 am

equations for q

Postby Jennifer Lathrop 1F » Sun Feb 10, 2019 5:05 pm

How do you know when to use q=nC(delta)T , q=mCdeltaT or just q=C(delta)T

Iris Bai 2K
Posts: 60
Joined: Fri Sep 28, 2018 12:18 am

Re: equations for q

Postby Iris Bai 2K » Sun Feb 10, 2019 5:33 pm

You use q=nC(delta)T when you are given the amount of moles, and q=mCdeltaT when you are given the mass, I don't think q=C(delta)T should really be used.

Jennifer Lathrop 1F
Posts: 71
Joined: Sat Dec 02, 2017 3:00 am

Re: equations for q

Postby Jennifer Lathrop 1F » Sun Feb 10, 2019 7:14 pm

Thank you!

005199302
Posts: 108
Joined: Fri Sep 28, 2018 12:15 am

Re: equations for q

Postby 005199302 » Sun Feb 10, 2019 7:21 pm

Always look at the units and how they cancel. That should indicate which to use.

Cameron_Greenberg_3C
Posts: 60
Joined: Fri Sep 28, 2018 12:26 am

Re: equations for q

Postby Cameron_Greenberg_3C » Sat Feb 16, 2019 9:02 pm

It depends on what the equation gives you. Usually the C(delta)T equation is only used in calorimeter problems. If you feel more comfortable with one or the other, you can easily convert between grams and moles with molecular weight.

Shibhon_Shepard
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Joined: Wed Nov 15, 2017 3:04 am

Re: equations for q

Postby Shibhon_Shepard » Wed Feb 20, 2019 1:35 pm

if its just the C(delta) T, you are already included the amount of moles, instead of adding it in the beginning.(aka when you only have one mole)

Jennifer Lathrop 1F
Posts: 71
Joined: Sat Dec 02, 2017 3:00 am

Re: equations for q

Postby Jennifer Lathrop 1F » Sun Mar 03, 2019 7:06 pm

Makes sense now, thank you!

Jack Hewitt 2H
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Re: equations for q

Postby Jack Hewitt 2H » Tue Mar 05, 2019 2:19 pm

q=nC(delta)T when given # of moles
q=mCdeltaT when given mass
q=C(delta)T when moles = 1

Jennifer Lathrop 1F
Posts: 71
Joined: Sat Dec 02, 2017 3:00 am

Re: equations for q

Postby Jennifer Lathrop 1F » Wed Mar 06, 2019 11:02 am

thanks!

Porus_Karwa_2E
Posts: 72
Joined: Fri Sep 28, 2018 12:24 am

Re: equations for q

Postby Porus_Karwa_2E » Mon Mar 11, 2019 7:38 pm

We use q=mCdeltaT when mass is given in grams. q=nCdeltaT when moles are given


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