Is a chocolate changing from solid to liquid chemical change?

Answer 1

Of course not, it is not a chemical change. A chemical change includes the change in the molecular structure of something. For example, a burning paper turns into ashes after a while. This is a chemical change because you cannot return the ashes into paper again, hence, a change in its chemical structure happened. As another instance, a cube of ice melts into water--it is a physical change because you can always return it into an ice by freezing it, but don't expect it to have it in its original shape. A melting chocolate undergoes a physical change.