A chemistry lab requires 4.5 liters of a solution that is 30% sodium chloride. The lab currently has a 60% sodium chloride solution. How many liters of the 60% solution must be diluted with water to achieve the desired concentration?

["How to Dilute a 60% Sodium Chloride Solution to Make 4.5 Liters of 30% Solution: A Step-by-Step Calculation", "If you’re working in a chemistry lab and need to prepare 4.5 liters of a 30% sodium chloride (NaCl) solution, but only have a concentrated 60% NaCl stock solution, dilution is essential. Understanding the mathematics behind this dilution process ensures accuracy—critical in scientific work. This article walks through the step-by-step dilution calculation and explains how to safely dilute the 60% solution with water to reach the exact desired concentration.", "---", "### Understanding the Dilution Formula", "The core principle behind dilution is the conservation of mass: the amount of solute remains constant, but the total volume increases when water is added.", "The dilution formula is:", "[\nC_1 \ imes V_1 = C_2 \ imes V_2\n]", "Where:\n- (C_1) = concentration of the stock solution = 60%\n- (V_1) = volume of stock solution needed (unknown)\n- (C_2) = desired concentration = 30%\n- (V_2) = final volume of diluted solution = 4.5 liters", "---", "### Step-by-Step Calculation", "1. Write the known values in the formula:", "[\n60% \ imes V_1 = 30% \ imes 4.5\ \ ext{liters}\n]", "2. Simplify the right side:", "[\n30% \ imes 4.5 = 0.30 \ imes 4.5 = 1.35\n]", "So the equation becomes:", "[\n60% \ imes V_1 = 1.35\n]", "3. Convert percentages to decimals for calculation (optional):\n60% = 0.60, so:", "[\n0.60 \ imes V_1 = 1.35\n]", "4. Solve for (V_1):", "[\nV_1 = \frac{1.35}{0.60} = 2.25\ \ ext{liters}\n]", "---", "### Conclusion: How Many Liters of 60% Solution Are Needed?", "You must dilute 2.25 liters of the 60% sodium chloride solution with water until the total volume reaches 4.5 liters, resulting in a final solution that is 30% sodium chloride—exactly the requirement.", "---", "### Why This Matters in the Lab", "- Precision: Accurate dilution ensures reliable experimental results and compliance with safety and protocol standards.\n- Safety: Working with highly concentrated chemicals demands correct dilution to prevent hazardous exposure or accidental reactivity.\n- Cost Efficiency: Using a stronger stock solution reduces waste and expense while achieving the target concentration.", "If you follow this calculation carefully, you’ll confidently prepare the correct solution for your lab’s needs.", "---", "### Quick Recap:\n- Desired volume: 4.5 L at 30% NaCl\n- Stock solution: 60% NaCl\n- Required volume of 60% solution: 2.25 liters\n- The rest (4.5 L – 2.25 L = 2.25 L) will be water", "By diluting 2.25 liters of 60% NaCl with 2.25 liters of distilled water, you achieve a precise, safe 30% solution.", "---", "Ready to make this dilution? Follow the formula, verify carefully, and always prioritize safety when handling laboratory chemicals."]