## equations for q

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

### equations for q

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

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

Thank you!

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

### Re: equations for q

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

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
Posts: 62
Joined: Wed Nov 15, 2017 3:04 am

### Re: equations for q

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

Makes sense now, thank you!

Jack Hewitt 2H
Posts: 67
Joined: Fri Sep 28, 2018 12:27 am

### Re: equations for q

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

thanks!

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

### Re: equations for q

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

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