Classify the following changes as physical or chemical. Even if you are incorrect in your assessment, you should be able to defend your choice. (a) Grape juice turns to wine. (b) Wood burns to ashes....

Classify the following changes as physical or chemical. Even if you are incorrect in your assessment, you should be able to defend your choice. (a) Grape juice turns to wine. (b) Wood burns to ashes. (c) Water begins to boil. (d) A broken leg mends itself.