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8 comments:
hello. may i know what is the frationating column used for?
What is the fractionating column used for ? what is the difference when a distillation set-up has a frationating column and when it doesn't?
A fractionating column is an essential item used in the distillation of liquid mixtures so as to separate the mixture into its component parts, or fractions, based on the differences in their boiling points.
Fractional distillation is used to separate mixtures of more than two liquids OR for two liquids whose boiling points are very close (difference in boiling points is less than 25°C) to each other. Hence when we use fractional distillation, we have to use the fractionating column.
What is an example of daily applications of crystallisation?
crystallisation is used to obtain a pure substance, right?
so how can it be pure if only most of the mixture is heated to evaporate, still leaving some of the other substance to cool along with the solid?
if iodine can dissolve in alcohol and not in water, can you dissolve the alcohol in the water after the iodine has dissolved in the alcohol?
isn't simple distillation almost the same as fractional distillation?
how do you remove the substance from the paper chromatography for testing for drugs/inks? or is the ink tested on the paper itself?
are indicators acidic, alkali or neutral?
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