In the technique of flame photometry: a. Molecules of the analyte are aspirated
ID: 1033470 • Letter: I
Question
In the technique of flame photometry:
a. Molecules of the analyte are aspirated into a flame where a small fraction of the molecules
is promoted to their excited state, from which they decay with the emission of characteristic
radiation.
b. The analyte is aspirated into a flame and promoted to the excited state by irradiation with
characteristic radiation, the absorption of which is measured.
c. The analyte is aspirated into a flame, in which it is atomised, and atoms, promoted to their
excited state, decay to the ground state with the emission of characteristic radiation.
d. A mercury analyte is subjected first to oxidation, then reduction, and the volatile elemental
mercury is vapourised in a stream of nitrogen, in which it absorbs light of a characteristic
energy.
e. A sodium, potassium or calcium analyte is subjected first to oxidation, then reduction, and
the volatile elemental analyte is vapourised in a stream of nitrogen, in which it absorbs light
of a characteristic energy.
Explanation / Answer
on the principle that an alkali metal salt drawn into a non-luminous flamewill ionise, absorb energy from the flame and then emit light of a characteristic wavelength as the excited atoms decay to the unexcited ground state. This is the basic principle of flame photometry
so the option 'a' is correct..