Download the .pdf file of the lab handout here.
Experimental Data and Results
*Make sure you show all work and calculations to receive full credit.
For each problem, find the ΔH for the target reaction below, given the following step reactions and subsequent ΔH values:
| Problem 1 | ||
|---|---|---|
| Target Reaction: | PCl5(g) → PCl3(g) + Cl2(g) | |
| Step Reactions: | P4(s) + 6Cl2(g) → 4PCl3(g) | ΔH = -2439 kJ |
| 4PCl5(g) → P4(s) + 10Cl2(g) | ΔH = 3438 kJ | |
| Answer______________ | ||
| Problem 2 | ||
|---|---|---|
| Target Reaction: | 2CO2(g) + H2O(g) → C2H2(g) + 5/2O2(g) | |
| Step Reactions: | C2H2(g) + 2H2(g) → C2H6(g) | ΔH = -94.5 kJ |
| H2O(g) → H2(g) + 1/2O2 (g) | ΔH = 71.2 kJ | |
| 2C2H6(g) + 7O2(g) → 4CO2(g) + 6H2O(g) | ΔH =-566 kJ | |
| Answer______________ | ||
| Problem 3 | ||
|---|---|---|
| Target Reaction: | N2H4(l) + H2(g) → 2NH3(g) | |
| Step Reactions: | N2H4(l) + CH4O(l) → CH2O(g) + N2(g) + 3H2 (g) | ΔH = -37 kJ |
| N2(g) + 3H2(g) → 2NH3(g) | ΔH = -46 kJ | |
| CH4O(l) → CH2O(g) + H2(g) | ΔH = -65 kJ | |
| Answer______________ | ||
| Problem 4 | ||
|---|---|---|
| Target Reaction: | H2SO4(l) → SO3(g) + H2O(g) | |
| Step Reactions: | H2S(g) + 2O2(g) → H2SO4(l) | ΔH = -235.5 kJ |
| H2S(g) + 2O2(g) → SO3(g) + H2O(l) | ΔH = -207 kJ | |
| H2O(l) → H2O(g) | ΔH = 44 kJ | |
| Answer______________ | ||
| Problem 5 | ||
|---|---|---|
| Target Reaction: | 2C2H4O(l) + 2H2O(l) → 2C2H6O(l) + O2(g) | |
| Step Reactions: | C2H6O(l) + 3O2(g) → 2CO2(g) + 3H2O(l) | ΔH = -685 kJ |
| C2H4O(l) + 5/2O2(g) → 2CO2(g) + 2H2O(l) | ΔH = -583.5 kJ | |
| Answer______________ | ||
| Problem 6 | ||
|---|---|---|
| Target Reaction: | N2(g) + 2O2(g) → 2NO2(g) | |
| Step Reactions: | N2(g) + 3H2(g) → 2NH3(g) | ΔH = -115 kJ |
| 2NH3(g) + 4H2O(l) → 2NO2(g) + 7H2(g) | ΔH = -142.5 kJ | |
| H2O(l) → H2(g) + 1/2O2(g) | ΔH = -43.7 kJ | |
| Answer______________ | ||
| Problem 7 | ||
|---|---|---|
| Target Reaction: | CO2(g) → C(s) + O2(g) | |
| Step Reactions: | H2O(l) → H2(g) + 1/2O2(g) | ΔH = 643 kJ |
| C2H6(g) → 2C(s) + 3H2(g) | ΔH = 190.6 kJ | |
| 2CO2(g) + 3H2O(l) → C 2H6(g) + 7/2O2(g) | ΔH = 3511.1 kJ | |
| Answer______________ | ||
| Problem 8 | ||
|---|---|---|
| Target Reaction: | N2H4(l) + CH4O(l) → CH2O(g) + N2(g) + 3H2 (g) | |
| Step Reactions: | 2NH3(g) → N2H4(l) + H2(g) | ΔH = 22.5 kJ |
| 2NH3(g) → N2(g) + 3H2(g) | ΔH = 57.5 kJ | |
| CH2O(g) + H2(g) → CH4O(l) | ΔH = 81.2 kJ | |
| Answer______________ | ||
| Problem 9 | ||
|---|---|---|
| Target Reaction: | 1/2H2(g) + 1/2Cl2(g) → HCl(g) | |
| Step Reactions: | COCl2(g) + H2O(l) → CH2Cl2(l) + O2(g) | ΔH = -47.5 kJ |
| 2HCl(g) + 1/2O2(g) → H2O(l) + Cl2(g) | ΔH = 105 kJ | |
| CH2Cl2(l) + H2(g) + 3/2O2(g) → COCl2(g) + 2H2O(l) | ΔH = -402.5 kJ | |
| Answer______________ | ||
| Problem 10 | ||
|---|---|---|
| Target Reaction: | C2H2(g) + 5/2O2(g) → 2CO2(g) + H2O(g) | |
| Step Reactions: | C2H6(g) → C2H2(g) + 2H2(g) | ΔH = 283.5 kJ |
| H2(g) + 1/2O2(g) → H2O(g) | ΔH = -213.7 kJ | |
| 2CO2(g) + 3H2O(g) → C2H6(g) + 7/2O2(g) | ΔH = 849 kJ | |
| Answer______________ | ||
| Problem 11 | ||
|---|---|---|
| Target Reaction: | HCl(g) + NaNO2(s) → HNO2(l) + NaCl(s) | |
| Step Reactions: | 2NaCl(s) + H2O(l) → 2HCl(g) + Na2O(s) | ΔH = 507 kJ |
| NO(g) + NO2(g) + Na2O(s) → 2NaNO2(s) | ΔH = -427 kJ | |
| NO(g) + NO2(g) → N2O(g) + O2(g) | ΔH = -43 kJ | |
| 2HNO2(l) → N2O(g) + O2(g) + H2O(l) | ΔH = 34 kJ | |
| Answer______________ | ||
| Problem 12 | ||
|---|---|---|
| Target Reaction: | Zn(s) + 1/8S8(s) + 2O2(g) → ZnSO4(s) | |
| Step Reactions: | Zn(s) + 1/8S8(s) → ZnS(s) | ΔH = -183.92 kJ |
| 2ZnS(s) + 3O2(g) → 2ZnO(s) + 2SO2(g) | ΔH = -927 kJ | |
| 2SO2(g) + O2(g) → 2SO3(g) | ΔH = -196.04 kJ | |
| ZnO(s) + SO3(g) → ZnSO4 (s) | ΔH = -230.32 kJ | |
| Answer______________ | ||