When you put a straw into a glass of water, the water rises over the straw. It is even higher than the water level in the glass. This is capillary action. The intermolecular attraction between water molecules and the adhesive force between the capillary walls and the liquid generate capillary motion. Further, there are many applications related to capillary actions. In this article, we will discover what the applications of capillarity are.
Meaning of Capillarity
The ascension of liquids via a tube or cylinder is known as capillary action. Adhesive and cohesive forces are responsible for capillarity.
The liquid moves higher because of interaction. The tube becomes narrower as the liquid level rises. The rise will accelerate if one of the two phenomena, surface tension or the ratio of cohesion to adhesion, rises. If the density of the liquid increases, the ascent of the liquid in the capillary will be slowed.
The quantity of water present in the capillary hinders the capillary’s ability to climb. The substance that surrounds the pores not only fills them but also coats them. The strongest adhesion is seen in solid materials that are closest to water molecules. The thickness of the film thickens as water is fed to the pore, and the amount of capillary force diminishes.
The film that formed on the outer surface of the soil molecules may also begin to flow. The movement of groundwater through different soil zones is done by capillary action. Capillary action is also used to transport fluids within plant xylem channels. When water evaporates from the surface of the leaves, this phenomenon pushes water up from the lower layers, which are the roots.
Responsible Forces for Capillary Action
Cohesion Forces
The force that occurs between the molecules of a liquid is known as cohesion. Before they fall to the ground, raindrops are bound together by the same force.
Surface tension is a well-known phenomenon, but few people realise that the concept of cohesion also contributes to it. Surface tension prevents things denser than liquids from sinking by allowing them to float on top of them without support.
Adhesion Forces
Another term that might be used to describe this phenomenon is adhesion. Adhesion is the force of attraction between two separate things, such as a solid container and a liquid. This is the same force that makes water stick to the glass’s surface.
Liquids moisten the surface of the solid with which they come into contact when adhesion is greater than cohesion, and the liquid bends upwards towards the container’s rim. Mercury and other non-wetting liquids have a larger cohesion force than adhesion force. Such liquids curve inwards when they approach the container’s rim.
Applications of Capillarity in Everyday Life
- Because of their low surface tension, lubricating oils spread freely across all surfaces.
- Cotton dresses are preferable in the summer because they feature fine pores that act as sweat capillaries.
- When detergents are used to wash clothes, the surface tension of the water is lowered, allowing dirt to be removed.
- Capillary action causes the entire towel to become wet if one end of a towel is dipped into a bucket of water and the other end hangs over the bucket.
- Water is delivered to the leaves at the apex of even the tallest trees by capillary rise.
- Waterproofing a fabric can be accomplished by including appropriate waterproofing ingredients into the fabric. As a result of this innovation, the fabric’s angle of contact is increased, making it waterproof.
- Capillarity causes a piece of blotting paper to absorb ink and a rag to absorb water.
- Capillarity causes the ink to rise in a pen or oil to rise up the wick of a lamp.
- Due to capillarity, sap rises from the tree’s roots and travels up the stem.
- The water beneath the soil rises to the surface due to capillary formation in the soil.
- The rise of moisture from the air in the pores causes wood to swell during the rainy season.
- Compared to clay, sand is drier soil. Because the gaps between the sand particles are not as tiny as those between clay particles, water cannot be drawn up by capillary action.
- The ink rises into the pores when it is laid over it.
- Capillary motion is also responsible for the increase of oil in a lamp’s wick.
Conclusion
The ascension of liquids via a tube or cylinder is known as capillary action. Adhesive and cohesive forces are principally responsible. Two forces are responsible for this action:
- Cohesion, which is a force that occurs between the molecules of a liquid.
- Adhesion, which is the force of attraction between two separate things, such as a solid container and a liquid.