A meniscus is what happens when you put a liquid into a container. When you put water in a beaker or test tube, you see a curved surface . With most liquids, the attractive force between the liquid and the container is greater than the attraction between the individual liquid molecules.
What is a water meniscus?
A meniscus is a curve in the surface of a molecular substance (water, of course) when it touches another material. With water, you can think of it as when water sticks to the inside of a glass. • Water Science School HOME • Water Properties topics •
When water is in a test tube it has a meniscus?
A concave meniscus, which is what you normally will see, occurs when the molecules of the liquid are attracted to those of the container . This occurs with water and a glass tube. A convex meniscus occurs when the molecules have a stronger attraction to each other than to the container, as with mercury and glass.
What causes a meniscus to form in a test tube?
Water experiences a force of adhesion with the polar glass molecules and so starts to wet and climb the walls of the test tube. ... Mercury does not experience an adhesion with glass and so the surface tension of mercury and its aversion to glass causes it to form an upward curving meniscus.
What is a meniscus and when do we use it?
This is the downward or upward curve at the surface of a liquid in a container. Depending on how the molecules of the liquid interact, this curve may either be concave or convex. A meniscus occurs because of surface tension in the liquid and must be read at eye level .
What is a meniscus how is it important in this experiment?
A meniscus is what happens when you put a liquid into a container . When you put water in a beaker or test tube, you see a curved surface. ... But if you always use the same method, and read from the bottom of the meniscus, you will have a constant way of doing it. That will help reduce errors in your experiments.
When mercury is kept in glass meniscus is?
Explain. Ans: Because cohesive force between molecules of mercury is greater than the adhesive force between mercury and glass molecules.
What is an example of meniscus?
The definition of a meniscus is the fibrous cartilage in a knee joint, or the curved upper surface of liquid that touches the sides of a jar, or a lens that is convex on one side and concave on the other. ... When oil is in a jar and the oil has a curve on the top of its surface , this is an example of meniscus.
What liquid has the lowest surface tension?
Hexane, C 6 H 14 , has the lowest surface tension of all the liquids given here. Hexane is a non-polar molecule, the only intermolecular forces acting between hexane molecules in the liquid will be the weakest of all the intermolecular forces, London forces (also known as dispersion forces).
What is the bubble on top of water called?
A: A meniscus is the curved surface at the top of a column of liquid. In a science class, this liquid is usually water or some sort of aqueous solution, and the column is usually a graduated cylinder or a pipet.
What determines the shape of a liquid’s meniscus?
When liquid water is confined in a tube, its surface (meniscus) has a concave shape because water wets the surface and creeps up the side . ... When liquid mercury is confined in a tube, its surface (meniscus) has a convex shape because the cohesive forces in liquid mercury tend to draw it into a drop.
What part of the meniscus do you read?
The key to getting an accurate reading, is to measure the center of the meniscus whether it be concave or convex. E.g. with a concave meniscus, measure the bottom of the meniscus and for convex meniscus, take the reading from the top of the meniscus.
What is upper meniscus?
The meniscus (plural: menisci, from the Greek for “crescent”) is the curve in the upper surface of a liquid close to the surface of the container or another object , caused by surface tension. It can be either concave or convex, depending on the liquid and the surface.
How do you read the colorless meniscus?
If the meniscus is convex, take your measurement at the highest point of the curve. The short answer: Take your measurement from the center of the meniscus . It’s that easy. Make sure to hold your container at eye level and read at the level of the center of the meniscus.
Why should one read the lower meniscus?
The lower meniscus must be read while measuring the volume of colourless or transparent liquids but the upper meniscus while using colured ones because the phase boundary in the colourless liquid is clearly visible so it is easy to read it.
