What does contact angle depend on?
The contact angle depends upon the medium above the free surface of the liquid, and the nature of the liquid and solid in contact. It is independent of the inclination of solid to the liquid surface. It changes with surface tension and hence with the temperature and purity of the liquid.
What is a high contact angle?
Contact angle is measured as the angle where a liquid or a vapor (but most often a liquid) interacts with a solid surface. A high contact angle (pictured right) indicates that the surface has low wetting – that is, the liquid droplet will not spread very much onto the surface.
When the angle of contact is zero then the meniscus is formed?
Shape of meniscus for a liquid of zero angle of contact is convex.
What will be the shape of liquid meniscus for angle of contact?
convex
How does angle of contact depend on the shape of liquid meniscus in a tube?
Answer: The angle made by the tangent drawn to the meniscus from the point of contact with the walls of the container measured from within the liquid is called the angle of contact. It depends on the atmospheric pressure, adhesive and cohesive forces of the liquid in the tube.
When the angle of contact is liquid The concave meniscus at the point of contact?
When a liquid has concave meniscus, the angle of contact is acute. When it has a convex meniscus, the angle of contact is obtuse. The angle of contact depends on the nature of liquid and solid in contact. For water and glass, B lies between 8° and 18°.
What is the shape of the meniscus if the angle of contact is a 90 B 90?
When angle of contact is less than 90°, the shape of meniscus is concave. When angle of contact is equal to 90°, the shape of meniscus is plain.
When the angle between surface tension with the liquid θ is greater than 90o the liquid becomes?
If θ is obtuse, i.e; θ >90°, then liquid meniscus will be convex upwards. If angle of contact is acute angle, i.e; θ <90°, then liquid will wet the surface.
What is the relation between surface tension and surface energy class 11?
So, surface tension of a liquid is equal to the work done in increasing the surface area of its free surface by one unit. In other words, surface tension is equal to surface energy per unit area.
When surface tension increases the angle of contact?
For the explanation of why it increases with increase in temperature, I found out that the surface tension causes the increase in cohesive forces and hence a upward concave. So when temperature rises, surface tension decreases and angle of contact increases.
When a detergent is added in water the angle of contact?
When the detergent is added with water then the angle of contact is decreased . Because small angle of contact will help in capillary rise of the water which will ultimately help in the detergent mixed water to mix up with the clothes at a faster rate . Aakash EduTech Pvt.
What will be the effect of increasing temperature on I angle of contact II surface tension?
(1) Effect of temperature : The surface tension of a liquid decreases with increasing temperature of the liquid. Hence, the angle of contact also decreases with increasing temperature of the liquid. For dissolved impurities, the surface tension increases linearly with the concentration of the dissolved materials.