The process of decreasing the concentration of a solution by adding more solvent while keeping the total amount of solute constant. Dilution is how laboratory solutions of precise concentrations are prepared from concentrated stock solutions.
Definition
The process of decreasing the concentration of a solution by adding more solvent while keeping the total amount of solute constant.
💡 Intuition
Watering down a drink—same amount of flavor, more liquid, weaker taste.
🎯 Core Idea
The moles of solute remain constant during dilution — only the volume and concentration change.
Example
Formula
Notation
M_1 and M_2 are the initial and final molarities (mol/L), V_1 and V_2 are the initial and final volumes. The product MV equals total moles of solute.
🌟 Why It Matters
Dilution is how laboratory solutions of precise concentrations are prepared from concentrated stock solutions. Pharmacists dilute medications to safe dosages, water treatment plants dilute chemicals for purification, and biologists prepare serial dilutions for cell culture experiments.
💭 Hint When Stuck
When solving dilution problems, apply M_1V_1 = M_2V_2 directly. First identify the known quantities — the initial concentration M_1, initial volume V_1, and either the final concentration M_2 or final volume V_2. Then solve for the unknown by rearranging the equation. Finally, check that your answer makes sense: diluting always decreases concentration and increases volume.
Formal View
Related Concepts
🚧 Common Stuck Point
Always add acid to water when diluting, never water to acid — the heat released can cause dangerous splashing.
⚠️ Common Mistakes
- Using the volume of solvent added instead of the total final volume — V_2 is the total volume of the final solution, not just the amount of solvent added
- Forgetting to match units — both volumes must be in the same unit (both mL or both L) for the equation to work
- Adding water to concentrated acid instead of acid to water — this is a safety hazard because the exothermic mixing can cause violent boiling and splashing
Go Deeper
Frequently Asked Questions
What is Dilution in Chemistry?
The process of decreasing the concentration of a solution by adding more solvent while keeping the total amount of solute constant.
What is the Dilution formula?
When do you use Dilution?
When solving dilution problems, apply M_1V_1 = M_2V_2 directly. First identify the known quantities — the initial concentration M_1, initial volume V_1, and either the final concentration M_2 or final volume V_2. Then solve for the unknown by rearranging the equation. Finally, check that your answer makes sense: diluting always decreases concentration and increases volume.
Prerequisites
Next Steps
Cross-Subject Connections
How Dilution Connects to Other Ideas
To understand dilution, you should first be comfortable with concentration. Once you have a solid grasp of dilution, you can move on to titration.
Visualization
StaticVisual representation of Dilution