A student is asked to prepare 25.0 g of aspirin (C9H8O4). She is also asked to use a 50.0% excess of salicylic acid (C7H6O3) when combining with acetic anhydride (C4H6O3) and expect to get a 65.0% yield in the reaction. How many grams of salicylic acid and of acetic anyhydride should she use? refer to the following reaction: 2 C7H6O3 + C4H603 -> 2 C9H8O4 + H20