Hello there, I am a little confused with the results I got after doing this coffee cup calorimetry experiment. If you could please review my formulas to see if I am doing everything properly I would be most appreciative.
For a reaction between baking soda and vinegar:
10.06 g of vinegar were used as well as 2.45 g of baking soda. Total mass is 12.51 g.
Temp(i): 17.2˚C
Temp(f): 16.6˚C
The ∆Hrxn, enthalpy of reaction was calculated by:
12.51 g * 4.148 J/g ˚C * (16.6˚C - 17.2˚C) = -31.41 J
-∆H = 31.41 J or 0.031 KJ This is an endothermic reaction
Now for covering the ∆Hrxn to a molar value:
10.06 g (1/60.05) = 0.17 mol
2.45 g (1/84.00) = 0.030 mol
Total molar mass = 0.20 mol
Then do ∆Hrxn / n
0.031 KJ / 0.20 mol = 0.155 KJ/mol
Again, if you could please tell me if I made any errors I would be very thankful.
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