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View Full Version : Question on Enthalpy (please help?)


smileshaikh
Feb 17, 2012, 06:42 AM
Hey guys. I just need some help on a lab that I did.

Pretty much this is a calorimetry lab. We had 30 ml of 2M NaOH inside of a calorimeter. And we added 30 ml of 2M HCL into the calorimeter. The product we got was water.

In my first trial here were my givens:

Volume of 2M NaOH used: 30ml
Initial temperature of NaOH: 24.8 degrees C
Volume of 2M HCL used: 30ml
Initial temperature of HCL: 24.5 degrees C
Final temperature reached: 38.1 degrees C
Total mass (volume) of mixture: 60ml
Temperature change, delta T: 13.6 degrees C for HCL/ 13.3 degrees C for NaOH
Heat flow, joules: -3740.544 (this is where I started getting confused. I calculated this value by using the formula: q= -{msdeltaT Cdelta T)
Moles of water produced: ?
Delta H (kj/mol water):?
Literature value: I know the literature value for the delta H should be -56 KJ, because the equation we used to get was doing the PRODUCTS-REACTANTS formula on H OH- ===> H20

So I got the delta H values for each and did the products minus reactions and got -56 KJ. That's the literature value. For my values, IDK how to do it. I know it's an conversion we have to do starting with ML and working our way with a mol to mol ratio, then using kj at the very end, but I just can't figure it out after so long. Please help.

smileshaikh
Feb 17, 2012, 07:08 AM
Please help, pretty pretty please.

smileshaikh
Feb 17, 2012, 08:22 AM
That person spammed me?