Purity, formulations and chromatography

Question 1

Purity on a chromatogram

Answer 1

All pure substances produce one spot

Impure substances produce 2 or more spots.

Question 2

Two substances are likely to be the same if:

Answer 2

Produce same number of spots in the same colour.

Spots ravel same distance up the paper.

Question 3

Rf values formulae

Answer 3

RF = Distance traveled by substance / Distance travelled by solvent

Question 4

Formulations method 1

Answer 4

Mass / Ar = moles
Divide by smallest to find ratio.
Write empirical formula

Question 5

Formulations method 2

Answer 5

Ar x atom number for each element and add up.
Mass / Total Ar.
Multiply X by formula.