A student titrating a sample of a powdered aspirin tablet to find out how much acetylsalicylic acid is in the sample finds that it requires 15.5 mL of a 0.109 M sodium hydroxide solution to neutralize the acid in the sample. How many milligrams of acetylsalicylic acid did the sample contain? Use the correct number of significant figures and do not include units or your answer will be counted wrong.

305 mg

Explanation:

The equation of the reaction is;

C9H8O4 + NaOH = C9H7O4Na + H2O

Amount of NaOH reacted = 15.5/1000 L * 0.109 M = 1.69 * 10^-3 moles

Since the reaction has a 1:1 mole ration, 1.69 * 10^-3 moles of acetylsalicylic acid reacted.

Assuming all the acetylsalicylic acid reacted, then mass of acetylsalicylic acid present = 1.69 * 10^-3 moles * 180.158 g/mol = 0.305 g or 305 mg

answer; /// the amount of material dissolved in a measure of liquid(concentration) the above statement is (true); /// good luck

let that person have a turn to speak : )