1 2 3

Mh x Ch x DeltaTh = Mc x Cc x DeltaTc

I need to isolate the varible Ch, and I can't seem to do it properly. Could somebody kindly give me a hand? Thank you!

___________________

*Edited by stapel -- Reason for edit: "language", punctuation, etc*

- Thread starter mathnubb
- Start date

1 2 3

Mh x Ch x DeltaTh = Mc x Cc x DeltaTc

I need to isolate the varible Ch, and I can't seem to do it properly. Could somebody kindly give me a hand? Thank you!

___________________

- Joined
- Feb 4, 2004

- Messages
- 15,943

Please reply with clarification. When you reply, please show how far you have gotten. Thank you.

Eliz.

. . .Mh: mass of hot metal

. . .Ch: heat capacity of hot metal

. . .DeltaTh: Change in temperature of Hot metal

. . .Mc: mass of cold water

. . .Cc: heat capacity of water

. . .DeltaTc: Change in temperature of Cold water

The "c" and "h" are just subscripts. The x's indicate multiplication.

I'm trying to isolate "Ch". When substituting values for the variables, I'm not ending up with a heat capacity anywhere near what I think the answer ought to be.

Using that equation above, I change the DeltaT's to "Tfc - Tic" and "Tfh - Tih", but since "Tf" for both the water and the metal are the same, the two can just be called "Tf". Then I make this long eqaution:

. . .MhChTf - MhChTih = McCcTf - McCcTic

The common factor is Ch; this is where I get lost.

. . .Ch(MhTf - MhTih) = McCcTf - McCcTic

. . .Ch = (McCcTf - McCcTic) / (MhTf - MhTih)

Then i would subststite values in to find Ch, but it always comes out negative. Any advice?

- Joined
- Feb 4, 2004

- Messages
- 15,943

. . . . .M<sub>h</sub> C<sub>h</sub> delta-T<sub>h</sub> = M<sub>c</sub> C<sub>c</sub> delta-T<sub>c</sub>

And you're wanting to solve for C<sub>h</sub>...?

Since all that's been done is multiplication, just divide off the other two factors:

. . . . .\(\displaystyle \L C_h\, =\, \frac{M_c C_c \Delta T_c}{M_h \Delta T_h}\)

Since we don't have the chemico-physical information (numerical values, chemical relationships, etc), we cannot speak to the answer(s) you are obtaining. Sorry.

Eliz.