Question

what kind of charge does a balloon have before it has not been rubbed on the wool cloth

Answer 1

Before a balloon is rubbed on a wool cloth, it generally has no net electric charge; it is electrically neutral. This means that the number of positive charges (protons) is balanced by the number of negative charges (electrons). When the balloon is rubbed on the wool cloth, it can gain electrons from the wool, resulting in a negative charge on the balloon. The wool, in turn, becomes positively charged due to the loss of electrons.