When a cleaned strip of zinc metal is placed in a solution of `CuSO_(4)`, a spontaneous reaction occurs, which of the following observation(s) is/are made?
A. The mass of zinc metal decreases gradually
B. The copper metal start depositing on either zinc plate or settles down the vessel
C. The solution remains electrically neutral
D. The temperature of the solution decreases as it is an endothermic reaction.
