I don't know what you call important and I'm inclined to believe that you could think of some things as well but here is one.
I put sugar in my milk and cereal in the morning. It's important to me that my cereal taste sweet and I don't want it to be solid and grind on my teeth so it's good for it to dissolve in the milk. How about an unconventional solution? How about air. Isn't it important that nitrogen and oxygen "dissolve" to give us the stuff we breathe? What about CO2 dissolving in soft drinks to give it the fizz (along with some of the taste although most of the taste comes from other ingredients).