in a paper chromatogram using ethyl alcohol, a dye spot is measured to move 13.8 cm from the origin.?

Question

in a paper chromatogram using ethyl alcohol, a dye spot is measured to move 13.8 cm from the origin.
The solvent front for that spot is measured to have moved 20.3 cm from the origin.

A) What is the Rf value for the dye spot?

B) From an independent paper chromatograph usin alcohol, the Rf values for teh following dyes are as follows:

Carmine Yellow-.59

Visual Purple-.67

Skyy Blue-.85

What is the likely identity of the dye spot whose Rf is calculated in a?

Answer 1

Rf= distance spot traveled from origin/distance solvent traveled

Rf means relative to front

In this case 13.8/20.3=0.67

Therefore the answer to part B is visual purple.