FORM 1-PHYSICS-STRUCTURE AND PROPERTIES OF MATTER
STRUCTURE AND PROPERTIES OF MATTER
The Concept of Capillarity
Explain the concept of capillarity
This is the tendency of a liquid to rise in narrow tubes or to be drawn into small openings such as those between the fibres of a towel. Capillarity can pull a column of liquid upward until the weight of liquid becomes greater than the surface tension.
In a tube, capillarity depends on the tube’s diameter but weight of water column depends on other factors besides it.
The smaller the radius of the tube the higher the liquid will rise in it. This implies that capillarity height is immensely proportional to the diameter of the tube.
By definition
Capillarity is defined as the tendency of liquid to rise in narrow tubes or to be drawn into small openings such as those between the fibres of a towel.
Capillarity action is the ability of a liquid to raise or fall in a narrow tube.
Note:
- Capillarity depends on the type of liquid. For example if you dip capillarity tube in water the water rises in the tube and above the level of the water in the vessel.
- If the tube is dipped in mercury, the liquid does not rise in the tube. It suffers capillarity depression.
Applications of Capillarity in Daily Life
Identify the applications of capillarity in daily life
The application includes:
- Capillarity is essential to plants and animals.
- In plants, it facilitates the transport of water and nutrients from the roots to the leaves where photosynthesis produces the plants food. In animals it assists in the circulation of blood.
- Capillarity promotes the movement of ground water.
- It is the principles on which paper and fabric towels work to absorb water.
- Cotton clothing in hot climates uses capillarity action to draw perspiration away from the body.
- In an oil or kerosene lamp capillarity draws the fuel up into the wicker where it can be burnt.
- A writing Rubin splits in the middle so that a fine capillary is formed
