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Although acetylsalicylic acid (aspirin) is a well-known and widely used analgesic and anti-inflammatory agent, copper(II) acetylsalicylate, a copper complex formed from aspirin and copper, has also been found to exhibit some distinctive and potentially beneficial pharmacological properties. Formation of copper(II) acetylsalicylate is achieved when the conjugate base of aspirin, acetylsalicylate (C₉H₇O₄⁻) , binds to Cu²⁺ ions in solution, as outlined in Reaction 1.4 NaC₉H₇O₄(aq) + 2 CuSO₄(aq) → Cu₂(C₉H₇O₄) ₄(s) + 2 Na₂SO₄(aq) Reaction 1Using Reaction 1, a researcher synthesized a sample of copper(II) acetylsalicylate for analysis. A small volume of 0.50 M aqueous copper(II) sulfate (molar mass = 159.6) was mixed into 100 mL of filtered, saturated aqueous sodium acetylsalicylate (molar mass = 202.2) at room temperature and slowly stirred. Formation of copper(II) acetylsalicylate (molar mass = 843.7) was immediately observed as a bright blue precipitate. The precipitate was then isolated by filtration and dried, affording the product complex in high yield.
Adapted from: Seguel GV, Rivas BL, Contreras JG. Synthesis and characterization of copper complexes: interaction of metalliccarboxylates with 1,3-thiazole ligand. Journal of the Chilean Chemical Society. 1970; 58(4) :1967.
-What volume of the copper(II) sulfate solution should be used in the reaction to deliver 0.8 g of CuSO₄ into the reaction mixture?

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11ecba2d_11cc_2a0b_a3bf_0de158f4b013_MD0008_00 The molar mass (molecular weight) is the amount of mass present in 1 mol of a substance, and it relates a given mass to the number of molecules present in a sample. The molarity of a solution is the number of moles of a substance present in 1 L of a solution. Therefore, the molar mass and the molarity relate to each other by the number of moles, and both can be used as conversion factors in chemical reaction calculations involving a given mass. If 0.8 g need to be delivered into the reaction, the number of moles in this amount of mass can be found by dividing by the molar mass of CuSO₄: (0.8 g) / (159.6 g/mol) = 0.005 mol CuSO₄ To find the volume of a 0.50 M solution required to obtain 0.005 mol CuSO₄ for delivery into the reaction, divide the number of moles by the molarity of the solution: (0.005 mol CuSO₄) / (0.50 mol/L) = 0.01 L CuSO₄ solution (Choice A) 1.6 mL is the value obtained if the mass is not converted to moles (dividing by molar mass) and is just divided by the molarity. Incomplete cancellation yields units of g·L/mol instead of units of volume. (Choice B) 2.5 mL is the value obtained if the mass is converted to moles but is then multiplied by the molarity (instead of dividing). Incorrect units of mol²/L result instead of units of volume. (Choice D) 0.40 L is the value obtained if the mass is not converted to moles and is instead multiplied by the molarity. Units of g·mol/L are obtained instead of units of volume. Educational objective: The molar mass expresses the mass present in 1 mol of a substance whereas the molarity of a solution expresses the number of moles of a substance dissolved in 1 L of a solution. The molar mass and the molarity relate to each other by the number of moles, and both can be used as conversion factors in chemical reaction calculations.

Passage Although Acetylsalicylic Acid (Aspirin) Is a Well-Known and Widely Used