Based on bond energies, which atmospheric gas in each pair do you think is more stable? Explain.

a. O₂ or N₂

b. CO or CO₂

In photosynthesis, green plants convert carbon dioxide and water into glucose (C₆H₁₂O₆) according to the following equation:

6 CO₂(g) + 6 H₂O(l) → C₆H₁₂O₆(aq) + 6 O₂(g)

a. Estimate ∆H for the reaction using bond dissociation energies from Table 7.1. Give your answer in kcal/mol and kJ/mol. (C₆H₁₂O₆ has five C―C bonds, seven C―H bonds, seven C―O bonds, and five O―H bonds).

In photosynthesis, green plants convert carbon dioxide and water into glucose (C₆H₁₂O₆) according to the following equation:

6 CO₂(g) + 6 H₂O(l) → C₆H₁₂O₆(aq) + 6 O₂(g)

b. Is the reaction endothermic or exothermic?

The following equation shows the conversion of aluminum oxide (from the ore bauxite) to aluminum:

2 Al₂O₃(s) → 4 Al(s) + 3 O₂(g) ∆H = +801 kcal/mol (+3350 kJ/mol)

c. How many kilocalories are required to produce 10.0 g of aluminum? How many kilojoules?