In a titration, a \(3.25 \mathrm{~g}\) sample of an acid, HX, requires \(68.8 \mathrm{~mL}\) of a \(0.750 \mathrm{M} \mathrm{NaOH}(\mathrm{aq})\) solution for complete reaction. What is the molar mass of the acid?

Titration analysis is a laboratory method used to determine the concentration of a solution, such as an acid or a base. By accurately measuring the volume of a known concentration of titrant added to a sample until the reaction reaches completion (the equivalence point), the unknown concentration of the sample can be calculated.

During a titration, indicators or pH meters may be used to pinpoint the endpoint, which indicates the equivalence point has been reached. A common titration, like the one in the textbook exercise, involves a strong acid and a strong base reaction. Precise calculations and measurements are crucial for a successful titration analysis, as they directly impact the accuracy of the final result.

Stoichiometry is the study of the quantitative relationships, or ratios of amounts, between substances involved in chemical reactions. It is based on the law of conservation of mass, where the total mass of reactants equals the mass of products.

For the exercises involving titrations, stoichiometry allows us to determine the moles of acid based on the moles of base used in the reaction. If no other information is provided, it is often safe to assume a 1:1 ratio for a reaction between a strong acid and a strong base, except when dealing with polyprotic acids or other complex reactions. Stoichiometry can be challenging for many students, but it forms the core of chemical calculations in reactions.

The molarity of a solution is a way of expressing concentration, defined as the number of moles of solute per liter of solution.The units for molarity are moles per liter (M). Calculating molarity involves knowing the amount of substance in moles and the total volume of the solution. Being essential for titrations, the concept of molarity is used to determine how much of the titrant should be added to the analyte to reach the endpoint. In our exercise, the molarity of sodium hydroxide (NaOH) plays a key role in finding the molar mass of the unknown acid.

Acid-base reactions are fundamental chemical reactions where an acid reacts with a base to produce water and a salt. This type of reaction is central to many titration problems. Understanding the nature of acids and bases, their strengths, and how they interact is vital.

As the strong acid HX reacts with the strong base NaOH, knowing the stoichiometry of the reaction allows us to deduce that the products will be water (H2O) and the salt NaX. The detailed comprehension of acid-base reactions is not only important for titration analysis but also has broader implications in various scientific and industrial applications, including environmental science, medicine, and materials science.