Exergonic, Endergonic and Entropy!

Can you explain how these are connected?

If the reaction is spontaneous (Exergonic) does this mean entropy should increase?

1. Oxygen and Hydrogen gases can be reacted together to form water. The entropy of the two gases is higher than the entropy of liquid water, so entropy seems to decrease. However, the reaction is spontaneous. Explain the apparent contradiction.

For any exergonic (spontaneous) reaction, the entropy of the universe will increase. It is very feasible that the entropy of the reacting system will decrease, but still, then entropy of the surroundings will increase more than the decrease in the entropy of the system. Freezing of water at below 0C is a very nice example. Obviously, this is a spontaneous process--you can witness it occurring. As liquid water freezes, entropy of the molecules of water molecules decreases a whole lot. However, in order to freeze liquid water, heat must be removed from the water. That heat increases the entropy of the surrounding air molecules more than the entropy of the water decreases. So, the total entropy of the universe does increase during this spontaneous process.

In this reaction, a whole lot of heat is released when H2 and O2 react to form liquid water. That heat raises the entropy of the molecules all around the water more than the entropy of the H2 and O2 decreases as it forms water.

That help?

Whenever there is a release of of heat, entropy increases because heat is the most disorganized form of energy.