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Why is it necessary to keep the beaker used for chromatography tightly covered?

The reason for covering the container is to make sure that the atmosphere in the beaker is saturated with solvent vapour. Saturating the atmosphere in the beaker with vapour stops the solvent from evaporating as it rises up the paper.

Why is water not a suitable solvent in paper chromatography?

Because the kind of compounfds that you try to determine using paper chromatography (organic compounds) are usually not soluble in water. Furthermore, water could react chemically with some of this compounds, because it’s a very reactive molecule. You need organic solvents that are mostly inert.

What happened to the water in the beaker?

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. So the liquid “sticks” to the side of the container. A few liquids have a “backwards” meniscus.

What is the beaker of water?

In laboratory equipment, a beaker is generally a cylindrical container with a flat bottom. Most also have a small spout (or “beak”) to aid pouring, as shown in the picture. Beakers are available in a wide range of sizes, from one milliliter up to several liters.

Whats the difference between a flask and a beaker?

Flasks are notable for their unique shape: a rounded vessel and a cylindrical neck. The main differing characteristic between a flask and a beaker is that beakers have straight sides, rather than slanted sides like a flask. Beakers are mainly for measuring and transporting liquids from one site to the next.

Why is a graduated cylinder better than a beaker?

A graduated cylinder is used routinely for measuring volume and is considered more accurate than a beaker because of the permanently-marked incremental graduations incorporated in the clear cylinder.