Question

At −73∘C, the process X⟶Y+Z has a standard free energy change of 11.5kJmol. What is the free energy change (in kilojoules per mole) at the same temperature with [X]=0.65 M, [Y]=1.8M, and [Z]=2.5M? The universal gas constant is 8.314Jmol K. Your answer should have three significant figures. (Round your answer to one decimal place). Do not include units in your answer.

Answer 1

To find the free energy change (ΔG) at -73°C with specific reactant and product concentrations, one must use the Gibbs free energy equation with the provided standard free energy change, the temperature in Kelvin, and the calculated reaction quotient (Q).

Step-by-step explanation:

The free energy change (ΔG) of a process at a specific temperature that is not the standard temperature can be calculated using the Gibbs free energy equation: ΔG = ΔG° + RTlnQ, where ΔG° is the standard free energy change, R is the universal gas constant, T is the temperature in Kelvin, and Q is the reaction quotient. In this case, ΔG° = 11.5 kJ/mol, R = 8.314 J/mol·K, T = -73°C (converted to Kelvin: T = 200.15 K), and the reaction quotient Q = ([Y]*[Z])/[X] = (1.8*2.5)/0.65.

Using these values, we can calculate ΔG as follows:

• First convert ΔG° into the same units as R: ΔG° = 11500 J/mol
• Calculate Q: Q = (1.8M*2.5M)/0.65M
• Calculate ΔG: ΔG = 11500 J/mol + (8.314 J/mol·K * 200.15 K * ln(Q))

Solving the equation gives us the free energy change at -73°C with the given concentrations of X, Y, and Z. To provide the final answer, one would perform these calculations and round to one decimal place as instructed.