Semiconductors made from elements in Groups 3A(13) and 5A(15) are typically prepared by direct reaction of the elements at high temperature. An engineer treats 32.5 g of molten gallium with 20.4 L of white phosphorus vapor at 515 K and 195Â kPa. If purification losses are 7.2% by mass, how many grams of gallium phosphide will be prepared?