Page 319 - SUBSEC October 2017_Neat

UNIT 2
MODULE 2: ANALYTICAL METHODS AND SEPARATION TECHNIQUES (cont’d)

SPECIFIC OBJECTIVES EXPLANATORY NOTES SUGGESTED PRACTICAL
ACTIVITIES

Mass Spectroscopy cont’d

Students should be able to:

7.3. use mass spectral data to: Use should be made of
mass spectral sheets.
(a) determine relative Refer to the (M+1 and M+2
isotopic masses; and peaks).
relative isotopic
abundance; and,

(b) distinguish between
molecules of similar
relative molecular
mass.

8. Chromatographic Methods of Separation

Students should be able to:

8.1. explain the theoretical These should be explained
principles upon which in terms of adsorption and
chromatographic methods partition between the
are based; mobile and stationary
phases; refer to paper,
column, thin layer and
gas-liquid chromatography.

8.2. explain the terms: retention
factor (Rf) and retention
time (tR); visualising agent;
solvent front;

8.3. describe the basic steps Use of R f values and The use of TLC to investigate
involved in separating and retention times in the mixtures and pure
quantifying the quantitation of substances compounds. (Plant extracts,
components of a mixture; is required. dyes and inks may be
considered. Visualisation
may be done using an iodine
chamber). Calculate R f
values.

CXC A11/U2/17 50