Volume to Volume (v/v)
Standard Calculation for Liquid Dilutions & Reagent Preparation
Required Solute:
0.00 mL
Instructions:
Add solute to flask, QS with solvent.
Calculated By (Operator):
Name:
Date:
Verified By (QA/Supervisor):
Name:
Date:
Understanding Percent Volume by Volume (% v/v)
Percent Volume by Volume (% v/v) is used when both the solute and the solvent are liquids. It expresses the volume of solute present in 100 mL of the total solution. This calculation is critical in pharmaceutical manufacturing for preparing reagents (e.g., 70% Ethanol, 5% Dextrose) and mobile phases for HPLC.
Calculation Scenarios
- Solute Volume: Calculates how much liquid ingredient to add to reach a desired total volume at a specific percentage.
- Percentage Strength: Determines the % concentration when mixing a known volume of solute into a total volume.
- Final Solution Volume: Determines the total volume you can prepare with a limited amount of solute at a specific percentage.
Key Formula
% v/v = (Volumesolute / Volumetotal) × 100
Note: Volumes are not always additive due to molecular interaction (volume contraction). Always "QS" (Quantum Satis) to the final mark.