Mon, 04 May 2026 22:26:25 +0000

A chemist has 5 beakers, each containing 150 mL of a 0.2 M NaCl solution. She pours all the solution into a large flask and dilutes it with 350 mL of water. What is the final concentration of the NaCl solution in the flask? This hands-on scenario, now widely explored in science education and DIY chemistry circles, reflects growing public interest in foundational chemistry practices—especially among learners, educators, and curious minds on the lookout for clear chemical principles. The simple dilution process isn't just a textbook example; it's a real-world method used to safely concentrate or reduce solutions in labs and classrooms across the US, highlighting how precise volume calculations guide practical science. The chemist’s procedure shows a classic dilution step: combining the total volume of 5 beakers—each with 150 mL at 0.2 M NaCl—requires careful volume summation before adding 350 mL of water. The total initial volume is 5 × 150 mL = 750 mL. Adding the water brings the final total to 750 mL + 350 mL = 1,100 mL, or 1.1 liters. Using the formula for dilution—Concentration × Volume = Constant—the final concentration equals initial concentration multiplied by the ratio of total volume after to before dilution. But how does this translate mathematically? Starting with 750 mL of 0.2 M solution: 0.2 M × 0.750 L = C₂ × 1.100 L Rearranging gives C₂ = (0.2 × 0.750) / 1.100 = 0.150 / 1.10 ≈ 0.136 M