chromotography Flashcards
1
Q
How do we calculate rf values?
A
= distance meoved by pigmenr/distance moved by solvent
2
Q
Why is the origin line drawn in pencil and not pen?
A
= ink from the pen would fissolve and run up the solvent
3
Q
why whpuld you draw the line where the solvent reached immediatly?
A
= solvent evaporates rapudly, so end position is ot shortlv visble, after the experiment
4
Q
why do we measure the rf value from the middle?
A
= pigmen mark is spread out, standardise the easurements
5
Q
Why do we make sure the chromtography paper is straight and vertical?
A
= to make sure pigments nove straight up the paper,
