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If a dye has a TLC Rf of 0.3 in a solvent 6:1 mixture of isopropyl...

If a dye has a TLC Rf of 0.3 in a solvent 6:1 mixture of isopropyl alcohol and concentrated ammonium hydroxide, how might you adjust the chromatography conditions to increase the Rf value?

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Answer #1

we know,

Rf = distance spot moves/ distance solvent moves.

If we increase the polarity of solvent mixture then the Rf value increases.

we have

isopropyl alcohol and concentrated ammonium hydroxide.

NH4OH is more polar in compare to isopropyl alcohol.

so

percentage of NH4OH increases in solvent mixture then Rf value increases.

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