Posted by Meenaakshi on .
500.0mL of 0.220 mol/L HCl(aq) was added to a high quality insulated calorimeter containing 500.0mL of 0.200mol/L NaOH(aq).Both solutions had a density of 1.000g/mL & a specific heat of 4.184 J/g.K. The calorimeter had a heat capacity of 850.0 J/degree C. The temperature of the entire system changes from 25.6 to 26.7C. Calculate dH in kJ/mole for NaOH.
I know the initial part of this problem.
q = mcdT
m of HCI = density X volume
= 1 g/ml X 500ml= 500 g
m of NaoH = 1g/mL X 500ml = 500 g
q = (500+500)(4.184)(1.1)
= 4602.4 J
Hope my approach is correct to this point.My problem is I don't know how to relate the heat capacity of calorimeter to the problem and how to find dH of NaOH eventually.
Need help. Thank you.

Chemistry 
DrBob222,
The calorimeter absorbs heat also; the way to handle that is to add it to the number you've calculated for the rest of the system.
4602.4 J + (Ccal x delta T) = 850 J/C * 1.1 = ? 
Chemistry 
Meenaakshi,
Ok,then how do I find the dH of NaOH? Do I need to use the total heat of the system and divide it by the mass of NaOH to get its dH ? I'm still confused
Thank you 
Chemistry 
Meenaakshi,
Sorry what I meant was dividing the total heat with mole of NaOH ,not mass.