For the reaction below g° = + 33.0 kj, h° = + 92.2 kj, and s° = + 198.7 j/k. estimate the temperature (k) at which this reaction becomes spontaneous. 2 nh3(g) → n2(g) + 3 h2(g)
a) 0.464k b)166k c)214k d)298k e)464k

D

Explanation:

A reaction becomes spontaneous when the value of the change in free energy is negative.

The relationship between the enthalpy, the entropy and the free energy in a chemical reaction is given below:

G = H – TS

Now, let’s input the values that we have.

One important thing to note is that we have to convert the KJ to Joules and this mean we have to multiply by a conversion factor of 1000. This mean 33KJ is 33,000J

33,000 = 92,200 - 198.7T

33,000 - 92,200 = -198.7T

-59,200 = - 198.7T

T = 59,200/198.7

T = 298k

law of conservation of matter