Question

2 H2O (l) → 2 H2 (g) + O2 (g)

1. Without doing any calculations, which side will enthalpy favor in this reaction? Entropy?

2. What volume of water in gallons would need to be split to store the same amount of energy as found in 10.0 gallons of gasoline? (Gasoline contains 44.4 MJ/kg, or 32.0 MJ/L, and has a density of 0.72 g/mL where 1 L = 0.2641775 gal).

Answer 1

delta Hrxn = (sum products)-(sum reactants)
This is not a calculation. You can see the products are zero since both are in their standard state and heat formation water is a negative number so delta H rxn is + and that means the left side is favored. Delta S should favor the right side.

Answer 2

Good job