Question

# Which of the following situations results in a spontaneous reaction? a. Entropy of the universe increases;...

Which of the following situations results in a spontaneous reaction?

a. Entropy of the universe increases; free energy of the system decreases.

b. Entropy of the universe decreases; free energy of the system decreases.

c. Entropy of the universe decreases; free energy of the system increases.

d. Entropy of the universe increases; free energy of the system increases.

I know the answer is A, (entropy of the universe increases; free energy of the system decreases), I just don't know why? Can someone please explain it to me? Thank you!!

delta G is used to check spontaneity

whenever delta G is negative, the reaction is spontaneous.

This is because, energy of system is decreasing and all compound want to have as less energy as possible

Entropy is measure of randomness. We know universe is expanding because it can increase the entropy that way. If we have two gases at two corners in a room, they will ultimately expand and full whole room because entropy will increase. This is law of nature to increase the entropy