In: Chemistry
Determine the calorimeter heat capacity using the known enthalpy of combustion of benzoic acid.
| 
 Sample  | 
 Tablet Weight(g)  | 
 Initial Temp(K)  | 
 Final Temp(K)  | 
 Wirelength(cm)  | 
 Wire left length(cm)  | 
| 
 Benzoic Acid  | 
 0.99  | 
 294.35  | 
 296.75  | 
 9.3  | 
 0  | 
| 
 Benzoic Acid(2)  | 
 1.01  | 
 295.25  | 
 297.85  | 
 9.3  | 
 0.8  | 
| 
 Naphthalene  | 
 .98  | 
 294.95  | 
 298.75  | 
 9.3  | 
 1.0  | 
| 
 Naphthalene(2)  | 
 1.07  | 
 295.05  | 
 301.95  | 
 9.3  | 
 0.5  | 
Determination of calorimeter heat capacity
moles of benzoic acid = 0.99 g/122 g/mol
= 0.008 mols
Enthalpy of combustion of benzoic acid = 3226 kJ/mol
So,
Heat released to calorimeter = 3226 kJ/mol x 0.008 mol
= 25.808 kJ
Heat capacity of calorimeter = 25.808/(296.75 - 294.35)
= 10.753 kJ/K