Capillary Action
| Formula / Notation | h = 2γ cosθ / (ρgr) |
|---|---|
| Also Known As | Capillarity, wicking, capillary rise, capillary depression |
What is Capillary Action?
Capillary action (capillarity) is the spontaneous rise or fall of a liquid in a narrow tube or porous material due to the interplay of adhesive forces (between liquid and tube) and cohesive forces (within the liquid) and surface tension. Water rises in glass capillaries because adhesion to glass exceeds cohesion. This phenomenon is important in plant water transport and chromatography.
Formula & Notation
Other Names / Synonyms: Capillarity, wicking, capillary rise, capillary depression
Properties & Characteristics
Uses & Applications
Safety Information
Always consult the SDS/MSDS before handling any chemical. This information is for educational purposes only.
Key Facts
Frequently Asked Questions
Capillary action (capillarity) is the spontaneous rise or fall of a liquid in a narrow tube or porous material due to the interplay of adhesive forces (between liquid and tube) and cohesive forces (within the liquid) and surface tension. Water rises in glass capillaries because adhesion to glass exceeds cohesion. This phenomenon is important in plant water transport and chromatography.
Capillary action drives water uptake in plants (xylem), blood flow in capillaries, ink absorption in paper, movement of fluids in thin-layer chromatography, and operation of wicking materials in textiles and medical devices. It is exploited in capillary electrophoresis and in microfluidic chips.
Capillary action can draw toxic or corrosive liquids through porous materials or along skin. Be cautious when capillary tubes containing hazardous liquids are handled. Ensure work surfaces and clothing do not wick up chemical spills.
The formula or notation for Capillary Action is: h = 2γ cosθ / (ρgr)