Nh3 is nitrogen trihydride (ammonia) and bf3 is boron trifluoride. what is the name for alcl3 and why? a) aluminum chloride - it does not have the prefix "tri-" since it is ionic. correct answer b) monoaluminum trichloride - there is only one aluminum and it needs the prefix "mono-". c) aluminum trichloride - it has the prefix "tri-" since it has the same ratio as the other compounds. d) aluminum chloride - ionic compounds do not get a prefix on the first name if there is only one of that element.