Question

is apple to apple juice reversible or irreversible?

Answer 1

Think about it. If you put an red apple (or a green apple) in a juicer and separate the liquid from the pulp, do you think you can put the juice back with the pulp, stir it around to mix thoroughly, and have a red or green apple pop out of the mixing bowl. I don't think so. I think you will still have a mixture of pulp and juice. By the way, everything I've described is a physical change. Solid water(ice) to liquid water is a reversible process depending upon which way the heat is going.