Exp. 12 Paper Chromatographic Separation of Food Dyes 2023 with 100% correct questions and answers

Chromatography is one of the most powerful methods of ________ separation of the components of a mixture Paper chromatography used in the experiment to -separate -identify food dyes present in mixture F D & C dyes stand for? Food Drug Cosmetic dyes The compounds of FD&C dyes have what 2 features in common? -contain conjugation in their bonding; alternating double and single bonds; their structural features leads to absorption of light in the visible region giving the dyes' colors -they all contain IONIC GROUPS such as (sulfonate, -SO3Na) or (carboxylate, -CO2Na) which dissociate to give SODIUM ION & ANIONIC GROUP upon dissolving in water The presence of the sodium ion & anionic group increase the _______ of the compounds since they make ________ interactions between DYE & SOLVENT WATER MOLECULES -WATER SOLUBILITY -ION-DIPOLE Chromatography allows the separation of the components of a mixture based on different properties, which are (3) -structure -ionic charge -molecular size The mixture in chromatography is transported in a ____ phase, as either a ___ or ___, which is in contact with a _____ phase -MOVING -gas -liquid -stationary A result of some molecules in mixture interacting more strongly with stationary phase than others is that they will not travel as rapidly as those molecules with WEAKER interactions to the stationary phase Species having _____ interactions w/ stationary phase will tend to travel at speeds newar that of the MOBILE phase WEAK The nature of ___ and _____ can be changed to allow the separation of complex mixtures -interaction -type of mobile & stationary phases In AFFINITY chromatography, separation is effected by the different affinity (the ability to bind or stick) of the components to the stationary phase while the mobile phase transports the components The two arrows -- --- depicts that the binding of a component to the stationary phase is not permanent The stronger the binding, the less time the component spends (solvated) in the moving mobile phase More strongly bound components are ___. We can describe the separation of the different components in terms of the ____ -RETAINED -DIFFERENCES IN RETENTION What is the solvated-bound reaction written like? component (solvated) -- -- component (bound) In this experiment, the stationary phase is PAPER -it is polar, contains a large number of -OH bonds Mobile phase travels up the paper, driven by capillary action If the component is not attracted to the stationary phase (equilibrium to the left), it would travel at the same rate as mobile phase If the compound is not soluble in the mobile phase (equilibrium to the right), it would not move with the mobile phase at all What is "spotting" the stationary phase? sample applied as solution to small spot of stationary phase & solvent is evaporated What are the 2 methods in identifying the unknowns in paper chromatography? -direct comparison w/ known substances -comparison of the relative retention factors, Rf The retention factor is the ratio of ratio of the distance traveled by COMPONENT to the distance traveled by the SOLVENT Rf(a) = d(a)/d(solvent) ... The Rf factor depends on the ___ & ___ phase -mobile -stationary 3 solvents available are -2-propanol -0.10% aqueous sodium chloride (NaCl) -water Good separation of dyes means that no two dyes migrate to the same extent