Weight to Volume (w/v)
Standard Pharmaceutical Calculation for Solutions & Reagents
Required Mass:
0.00 g
Instructions:
Dissolve solute in solvent to volume.
Performed By:
Name:
Date:
Checked By:
Name:
Date:
Understanding Percent Weight by Volume (% w/v)
Percent Weight by Volume (% w/v) is one of the most common expressions of concentration in pharmaceutical science. It represents the number of grams of a solid solute dissolved in 100 mL of total solution.
Calculation Scenarios
- Mass Required: Calculates how many grams of Active Pharmaceutical Ingredient (API) or excipient are needed to prepare a specific volume of solution at a certain percentage.
- Percentage Strength: Determines the % concentration when a known mass of solute is dissolved in a known volume.
- Final Volume: Calculates the total volume of solution that can be prepared with a limited amount of solute at a target percentage.
Key Formula
% w/v = (Masssolute (g) / Volumesolution (mL)) × 100
Common Example: Normal Saline (0.9% w/v NaCl) contains 0.9g NaCl in 100mL solution.