Thanks C. Enthalpy (Heat) of Solution for the Dissolution of a Sal Trial 2 of sa

ID: 590539 • Letter: T

Question

Thanks C. Enthalpy (Heat) of Solution for the Dissolution of a Sal Trial 2 of salt Trial I 5 1. Mass of salk (g) 2. Moles of salt (mol) 3. Mass of calorimeter (g) 4. Mass of calorimeter+ waie e) a oml H2 o 5. Mass of water (g) 6. Initial temperature of waterC 7. Final temperature of mixture from graph O 8. Instructor's approval of graph 13 .97 11.47 9.5 Calculations for Enthalpy (Heat) of Solution for the Dissolution of a Salt 4.1 15.9 I. Temperature change of solution, TCO 2 Heat change of water 3. Heat change of salt() (Otain its specific heat from Table 251 4. Total enthalpy change (U) SPeahc heas 5. 11.Minol sar), equation 25.12 6. Average AH, (Wimol salr) 25.1.).11S 1.57 "Optional. See instructor. *Show caleulations for Trial 1. Report the result with the correct number of significant figures 51 /53,0 , 093 1s 1 124,8 e) eL.lyll x 19.87%, 14, 1) _ (-1.578 5 x Experiment 25 303

Explanation / Answer

Trial 1

Trial 2

4. Total Enthalpy Change, (J)

(1160.6 + 115.4) = 1276.0

(1162.2 + 124.8) = 1287.0

5. Hs, (kJ/mol salt)

-(1276.0 J)/(0.0934 mol)*(1 kJ/1000 J) = -13.662 kJ/mol

-(1287.0 J)/(0.0934 mol)*(1 kJ/1000 J) = -13.779 kJ/mol

6. Average Hs, (kJ/mol)

½*[-(13.662 + 13.779)] kJ/mol = -13.7205 kJ/mol