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Why is it important to stop the chromatograph before the solvent reaches the top of the paper?
Wiki User
∙ 10y ago
if it wouldn't be above the level of solvent the spots will run off
Wiki User
∙ 15y ago
Wiki User
∙ 13y agoHaving solvent levels below the origin give a more accurate spread of colours, as the water is allowed to begin properly soaking and ink is not lost in the solution upon direct contact. Also, there is little to no motion through the paper below the solvent level and hence, the ink/dye won't be able to travel up the chromatography paper.
Wiki User
∙ 13y agobecause it will just end up dissolving in to the solvent and run of the paper before it even gets a chance to soak it's way up the paper.
Wiki User
∙ 10y agobecause you won't be able to calculate the RF since you don't know what's the distance from the origin to the solvent front.
Wiki User
∙ 11y agoif the solvent front would be above the spot of dyes, than the dyes would washed out in solvent and would not be able to move.
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Why do we crush solids before putting them into a solvent?
to increase the surface area of the solute
Why do you crush solids before putting them into a solvent?
To increase the surface area of the solute, which allows it to dissolve faster.
What is the solute and solvent of jelly?
The solvent of jelly is water and the solute is jelly powder :) Hope it helped !
Why should the jar used to develop TLC plates be covered?
The jar should be covered so that it is saturated with the vapours of the volatile solvent before the plate is allowed to run.
What is the name of the solid residue remaining after evaporation?
Any residue present after evaporation of a solvent must have been either dissolved in the solvent, [by definition, permanently] suspended in the solvent, or a precipitate lying on the bottom of the solvent container, assuming that the solvent had not been disturbed for at least two hours. Regulatory samples, such as environmental samples taken from a lake or river for analysis, are typically shaken or stirred immediately before being passed through a filter with a 100 to 200 micron (micrometer) pore size to catch any precipitated solids. Weighing the filter before and after it has been used and allowing it to thoroughly dry will yield the mass of any precipitated solids. The first filtering is not always performed, and if it is, a filter with a larger pore size is sometimes used. These things depend on the specific procedure being followed and may also depend on whether there are any visible precipitated solids after the sample has been left undisturbed for several hours. Assuming that no precipitated solids are present or that the sample is either centrifuged or allowed to settle before some of it is carefully decanted off for further analysis, the only way to distinguish the mass of any suspended solids vs. the mass of any dissolved solids is to pass the sample through a filter with a 0.45 micron, or smaller, pore size. A filter with that small of a pore size will capture virtually anything suspended in a solvent. The mass of any suspended solids present may be determined by comparing the dried filter's mass before and after filtration. Comparing the mass of a sample dish containing an aliquot of the filtrate (the solvent that was filtered) before and after the solvent was allowed to completely evaporate allows the analyst to determine the percentage of dissolved solids.
Why do you think it is important to clean water before it reaches towns and cities?
Contaminated water can spread many diseases, such as cholera.
Which organ is most important?
All of the organs are very important. The most important is probably "the big organ" which is your intestinal organ. That is what the food eaten goes through after it is broken up, but before it reaches the toilet.
Why is it important that the sample spots are not below the solvent level when the filter paper is first placed in the developing chamber?
By placing the spot above the level of the solvent in the beaker, you slow the flow of solvent which results in improved separation of the components in the spot. If you placed it below the level of the solvent in the beaker, the solvent would just flow at a much faster rate and instead of separating the components in the spot, they would simply be washed away.
What would the name of a developing tornado be before it reaches the ground?
Before it reaches the ground a developing tornado is known as a funnel cloud.
What would the name of a developing tornado be before it reaches to the ground?
Before it reaches the ground a developing tornado is known as a funnel cloud.
What is the name when magma reaches the surface?
Magma is liquid rock before it reaches the surface magma which reaches the surface is called lava.
Some precipitation never reaches the earth because?
it evapourates again before it reaches the ground
How do you make a sentence out of solvent?
Always test the solvent on a small hidden place on the garment before applying it to the stain. A man who is not financially solvent should not ask a woman to marry him.
Before molten rock reaches the surface it is called what?
Before lava reaches the surface it is called magma.
How far does cocoa have to be transported before it reaches the UK?
how far does cocoa beans have to travel till it reaches the UK
What important part stones play a role in an ostrichs digestive system?
it plays an important role because the stones wind up the birds gizzard, a pace which helps to grind the birds food, before it reaches the intestines.
Why must you record both the solute and solvent when discussing solubility?
You want to be able to know what solute and what solvent you are using before you start talking about a solubility.
