Which of the following processes are spontaneous?

a. melting H₂O(s) at 25°C
b. melting H₂O(s) at -25°C
c. a tree growing
d. the sun providing light and energy and a tree growing

If spontaneity depends on disorder, why do we need to consider H?

Use the data provided to find the standard molar entropy change for the reaction below.

SiO₂(s) + 2 C(graphite) ---> Si(s) + 2 CO(g)

S° values are: SiO₂(s) = 0.04 kJ/mol•K, C(graphite) = 0.01 kJ/mol•K, Si(s) = 0.02 kJ/mol•K, and CO(g) = 0.20 kJ/mol•K.

Use the standard free energy of formation data provided to determine G° for the reaction below.

SO₂(g) + 2 H₂S (g) ---> 2 H₂O(g) + 3 S(s)

G_f° values are: SO₂(g) = -3.0 x 10² kJ/mol, H₂S = +0.3 x 10² kJ/mol, H₂O(g) = -2.4 x 10² kJ/mol, and S(s) = 0 kJ/mol.

How are G and G° related?

a. G° is G for the reactants and products in standard states.
b. G is used to determine spontaneity and G° is used for equilibrium.
c. G° is G when Q = 1.
d. G° is temperature dependent and G is not.

Give the thermodynamic equilibrium constant expression for the reaction below.

2 Ag⁺(aq) + H₂O₂(aq) <==> 2 Ag(s) + 2 H⁺(aq) + O₂(g)

Which will cause greater tendency of the process to occur in the forward direction?

4 KO₂(s) 2 CO₂(g) <==> 2 K₂CO₃(s) + 3 O₂(g)

Which quantities depend on temperature in the relationship G° = H° + TS°?

The maximum quantity of energy available for useful work is

Consider the reaction:

N₂O₄(g) <==> 2 NO₂(g)

K_eq = 0.1134 at 20°C, and the change in enthalpy of the reaction is 58.03 kJ/mol. (a) What is the standard change in free energy for this reaction at 20° in kJ/mol? and (b) Determine the standard change in entropy for this reaction in J/mol-K.