specific heat question?

Question

when 10.0 mL oof a 1.00 M AgNO3 solution is added to 10.0 mL of 1.00 M NaCl solution at 25C is added to a calorimeter, the temperature raises to 32.6C. If the specific heat of the mixture is 4.18J/gC and the density is 1.00 g/mL, what is the Specific Heat for the reation....

What I did:
I used Mass x specific heat x temperature change
I took 20.00g x 4.18 X 7.4=618.64
since qrxn=-qcal, it should be -618.64J,
or -.61864 kJ

first of all, did I calculate the mass correctly, and secondly, did I do the problem right?

I think there is another step after what I have already done, since I found specific heat, but not for the reaction? I am confused by the wording of the problem.

Answer 1

The temp rise is 7.6 oC and not 7.4 oC

The question should read (I think) what is the enthalpy of the reaction. Specific heat is an attribute of a substance and not that of a reaction.

Assuming this is the case, the reaction is exothermic (gives out heat) and so the enthalpy will have a positive sign

Enthalpy is normally expressed as kJ/mol. You have 0.01 mol of AgNO3 and NaCl so the answer will be

(10 +10) x 1 x 4.18 x (32.6 - 25) / 0.01 or 63.5 kJ/mol

Answer 2

The mass is 20ml *1g/ml = 20g. It looks like you did it right.

Answer 3

Send this question to VTU ....it will be next vtu paper! dont worry about branch...any branch is ok???