Final answer:
The charge for gold in AuCl3 is +3, as the three chloride ions each have a -1 charge, and the compound as a whole is neutral.
Step-by-step explanation:
The charge for gold in the compound AuCl3 can be determined by looking at the charges of the chloride ions. Chlorine typically forms a -1 charge when it becomes an ion. Since there are three chlorine ions in AuCl3, the total negative charge is -3. To balance this, gold must have a +3 charge, making the gold ion Au3+. This is due to the compound being neutral overall, so the charges of the gold and chlorine ions must balance out to zero.