(a)
Interpretation:
Difference between wall-coated, support-coated, and porous-layer open tubular columns for gas chromatography has to be explained.
Concept Introduction:
In
(a)

Explanation of Solution
In wall-coated open tubular column, liquid stationary phase is bonded to the wall of column. In support-coated open tubular column, liquid stationary phase is bonded to solid support on wall of column.
While porous layer open tubular column, solid stationary phase is bonded to wall of column.
(b)
Interpretation:
Advantage of bonded stationary phases in the gas chromatography has to be explained.
Concept Introduction:
Refer to part (a).
(b)

Explanation of Solution
Bonded or cross linked stationary phase reduces the tendency of the tendency for the stationary phase to bleed from the column during the entire process.
(c)
Interpretation:
Use of makeup gas in for some gas chromatography detectors has to be explained.
Concept Introduction:
Refer to part (a).
(c)

Explanation of Solution
Makeup gas is used in gas chromatography to sweep the components through a detector to minimize the band broadening.
(d)
Interpretation:
Work of solvent trapping and cold trapping in splitless injection has to be explained.
Concept Introduction:
Refer to part (a).
(d)

Explanation of Solution
In solvent trapping, initial column temperature is low enough to condense solvent at the beginning of the column. Solute is very soluble in the solvent and is trapped in a narrow band at the start of the column.
In cold trapping, initial column temperature is around
In both cases, elution occurs as the column temperature is raised.
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Chapter 22 Solutions
EXPLOR. CHEM ANALYSIS (LL) - W/ ACHIEVE
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