Question

Using your data from Exercise 1 (Data Tables 1, 3, & 5), first calculate the heat loss or heat gain for each of the 3 solution mixtures (q_rxn). Then calculate the ?H for each reaction. Show your calculations.

Rxn 1: NaOH(aq) + HCl(aq) Ã H₂O(l) + NaCl (aq)

Rxn 2: NaOH(aq) + NH₄Cl(aq) Ã NH₃(g) + NaCl(aq) + H₂O(l)

Rxn 3: NH₃(aq) + HCl(aq) Ã NH₄Cl(aq)

Data Table 1. Temperature (°C) of the Solution (NaOH + HCl).

Initial Temperature of NaOH (°C)	22.6°C
Initial Temperature of HCl (°C)	23.1°C
Average Initial Temperature of Two Separate Solutions (°C)	22.85°C
Highest Temperature of Mixture (May need to be extrapolated from graph; see the example on p. 7-8 of the procedure) (°C)	35.3°C
Change in Temperature of Mixture (°C; this is the “highest temp of mixture” – “average initial temp of the two separate solutions”), ?T	12.5°C

Data Table 2. Temperature of Solution Every 20 Seconds.

Time after mixing (min:sec)	Temperature (oC)
Initial	30.8
0:20	34.2
0:40	35.0
1:00	35.2
1:20	35.3
1:40	35.3
2:00	35.2
2:20	35.1
2:40	35.1
3:00	34.9
3:20	34.8
3:40	34.7
4:00	34.6
4:20	34.4
4:40	34.3
5:00	34.1

Data Table 3. Temperature (°C) of the Solution (NaOH + NH₄Cl).

Initial Temperature of NaOH (°C)	22.7°C
Initial Temperature NH4Cl (°C)	24.0°C
Average Initial Temperature (°C)	23.35°C
Highest Temperature of Mixture (May Be Extrapolated from Graph) (°C)	24.5°C
Change in Temperature of Mixture (°C), ?T	1.1°C

Data Table 4. Temperature of Solution Every 20 Seconds.

Time after mixing (sec)	Temperature (oC)
Initial	24.5
0:20	24.4
0:40	24.3
1:00	24.2
1:20	24.1
1:40	24.1
2:00	24.0
2:20	24.0
2:40	24.0
3:00	23.9
3:20	23.9
3:40	23.9
4:00	23.9
4:20	23.9
4:40	23.9
5:00	23.8

Data Table 5. Temperature (°C) of the Solution (NH₃ + HCl).

Initial Temperature of NH3 (°C)	23.0°C
Initial Temperature HCl (°C)	24.1°C
Average Initial Temperature (°C)	23.55°C
Highest Temperature of Mixture (May Be Extrapolated from Graph) (°C)	29.6°C
Change in Temperature of Mixture (°C), ?T	6.0°C

Data Table 6. Temperature of Solution Every 20 Seconds.

Time after mixing (sec)	Temperature (oC)
Initial	24.5
0:20	28.7
0:40	29.4
1:00	29.6
1:20	29.5
1:40	29.5
2:00	29.5
2:20	29.4
2:40	29.4
3:00	29.4
3:20	29.3
3:40	29.2
4:00	29.2
4:20	29.1
4:40	29.12
5:00	29.1

I have 10ml of each solution.