Why lower meniscus is read when the burette is filled with HCL while upper meniscus is read when the burette is filled with potassium permanganate solution?
Table of Contents
- 1 Why lower meniscus is read when the burette is filled with HCL while upper meniscus is read when the burette is filled with potassium permanganate solution?
- 2 Which part of the meniscus should the volume be measured from?
- 3 What is the bottom of the meniscus?
- 4 Why do we read from the upper meniscus when dealing with dark colored or opaque liquid?
- 5 What is lower meniscus?
- 6 What property of water causes meniscus?
Why lower meniscus is read when the burette is filled with HCL while upper meniscus is read when the burette is filled with potassium permanganate solution?
Ans. Because it is easy to read the lower meniscus in case of colourless solutions, while the upper meniscus in case of coloured solutions.
Which part of the meniscus should the volume be measured from?
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 the bottom of the meniscus?
Reading a Meniscus For a concave meniscus, the volume of the liquid in the container is read from the bottom of the curve. You may notice a ‘line’ of liquid at the very top, forming the curve itself. The bottom of the curve is the lower side of this line.
Why do we need to read the lower meniscus and not the upper meniscus?
Lesson Summary A meniscus occurs because of surface tension in the liquid and must be read at eye level. For a concave meniscus, the correct volume will be read at the bottom of the curve. For a convex meniscus, the opposite is true and the correct reading will be at the top of the curve.
Will you read upper or lower meniscus of KMnO 4 solution in a burette?
Since the solution of KMnO4 is of dark colour, the upper meniscus should be considered for noting the burette readings.
Why do we read from the upper meniscus when dealing with dark colored or opaque liquid?
A meniscus is the curvature of the surface of the water. However, in the case of coloured liquids observing this phase boundary (spatial interface, called a phase boundary) is not possible, hence only the upper meniscus is considered.
What is lower meniscus?
What property of water causes meniscus?
Why a meniscus occurs Adhesion is responsible for a meniscus and this has to do in part with water’s fairly high surface tension. Water molecules are attracted to the molecules in the wall of the glass beaker.