gen-briefly-explain-molarity-and-dilution-and-one-common-misconc-8410

Briefly explain molarity and dilution and one common misconception about it.

# Molarity and Dilution **Molarity** is a measure of concentration defined as moles of solute per liter of solution (mol/L or M). For example, a 2 M NaCl solution contains 2 moles of NaCl in every liter of solution. **Dilution** is the process of decreasing concentration by adding more solvent. The key principle is that the number of moles of solute remains constant during dilution, expressed by: **M₁V₁ = M₂V₂** where M = molarity and V = volume (initial and final). ## Common Misconception **"To make a 1 L solution of specific molarity, add the solute to 1 L of solvent."** This is **incorrect**. You should dissolve the solute in *less* than the final volume of solvent, then add solvent *until* the total solution reaches the desired final volume (e.g., 1 L). Adding solute to a full liter of solvent will result in a final volume greater than 1 L, making your solution less concentrated than intended. **Correct approach**: To make 1 L of 1 M NaCl, dissolve 58.5 g of NaCl in ~800 mL of water, then add water until the total volume reaches exactly 1 L.