Styrene is produced by catalytic dehydrogenation of ethyl- benzene at high temperature in the presence of superheated steam.

Given the following data,

Ethylbenzene, C6H5--CH2CH3 :

delta Ht = -12.5 kJ/mol,

delta Gt = 119.7 kJ/mol and

S = 255 J/mol*K

Styrene, C6H5--CH==CH2 :

delta Ht = 103.8 kJ/mol,

delta Gt = 202.5 kJ/mol

and S = 238 J/mol*K

(a) Find ÄH°rxn, ÄG °rxn, and ÄS °rxn, given these data at 298 K: answer 116.3 kj, 82.8 kj, 114 j/k

(b) At what temperature is the reaction spontaneous? answer 747C

C)What are Delta G (answer 16.8 kj/m )

and K at 600 degrees?

Note: I only need help with K at 600 degrees. Thank you.

I thought it was 9.9 x 10^2 but it was marked wrong

I get 0.0988. I think you dropped the - sign AND you are allowed more than two significant figures in the answer.

To determine the value of K at 600 degrees for the reaction, we need to use the equation:

ΔG = -RT ln(K)

Where ΔG is the change in Gibbs free energy, R is the gas constant (8.314 J/mol*K), T is the temperature in Kelvin, and K is the equilibrium constant.

First, convert the temperature from Celsius to Kelvin:
600°C + 273.15 = 873.15 K

Now, rearrange the equation and solve for K:
K = e^(-ΔG /RT)

Substituting the given values:
ΔG = 16.8 kJ/mol = 16,800 J/mol
R = 8.314 J/mol*K
T = 873.15 K

K = e^(-16,800 / (8.314 * 873.15))

Using a calculator or mathematical software, calculate the value of K, which is approximately 4.52 x 10^-42.

Therefore, the value of K at 600 degrees is approximately 4.52 x 10^-42.

To find K at 600 degrees, we can use the equation:

ΔG° = -RTln(K)

where ΔG° is the standard Gibbs free energy change, R is the gas constant (8.314 J/mol·K), T is the temperature in Kelvin, and K is the equilibrium constant.

First, we need to convert the temperature to Kelvin:

600 degrees Celsius = 873 Kelvin

Now we can rearrange the equation to solve for K:

K = e^(-ΔG° / RT)

Substituting the values:

ΔG° = 16.8 kJ/mol = 16,800 J/mol
R = 8.314 J/mol·K
T = 873 K

K = e^(-16,800 / (8.314 * 873))

Calculating this expression:

K ≈ 2.43 × 10^-3

Therefore, the equilibrium constant (K) at 600 degrees Celsius is approximately 2.43 × 10^-3.