Question 1
Calculate the energy change for the formation of LiCl(
s) from its elements in their standard states and the following tabulated information:
| Li(s) + 1/2 Cl2(g) → LiCl(s) | ? |
| Li+(g) + Cl-(g) → LiCl(s) | -853 kJ/mol |
| Li(s) → Li(g) | +159.4 kJ/mol |
| 1/2 Cl2(g) → Cl(g) | +121.7 kJ/mol |
| Cl(g) + e- → Cl-(g) | -348.6 kJ/mol |
| Li(g) → Li+(g) + e- | +520.2 kJ/mol |
◦ -400.3 kJ/mol
◦ +1305.7 kJ/mol
◦ -627.2 kJ/mol
◦ +296.9 kJ/mol
Question 2
Calculate the lattice energy for NaCl(
s) using a Born-Haber cycle and the following information:
| NaCl(s) → Na+(g) + Cl-(g) | ? |
| Na(s) + 1/2 Cl2(g) → NaCl(s) | -411.0 kJ/mol |
| Na(s) → Na(g) | +107.3 kJ/mol |
| Na(g) → Na+(g) + e- | +495.8 kJ/mol |
| 1/2 Cl2(g) → Cl(g) | +121.7 kJ/mol |
| Cl(g) + e- → Cl-(g) | -348.6 kJ/mol |
◦ +787.2 kJ/mol
◦ +34.8 kJ/mol
◦ +1512 kJ/mol
◦ +690.3 kJ/mol
Examples of energy
Fossil Fuels Energy Yield and Pollutants—Comparison
Cuba’s Energy Geopolitics
The Citric Acid Cycle
Reactions of the glyoxylate cycle
The cycle of G protein dissociation and reassociation