Gas Chromatography

Question: Derivatisation of a sample is carried out to
[A].

reduce polarity of the analytes

[B].

increase the detector response

[C].

increase volatility of the analytes

[D].

all of the above

Answer: Option D

Explanation:

No answer description available for this question.

Question: Headspace analysis is carried out in order to
[A].

analyse volatile compounds from solid or liquid samples

[B].

determine the psychological state of the tutor

[C].

analyse the column contents ahead of the sample

[D].

determine non-volatiles

Answer: Option A

Explanation:

No answer description available for this question.

Question: In column switching chromatography
[A].

compounds trapped on one column are eluted to another column

[B].

one column is removed and replaced by another

[C].

the flow to the column is switched on and off repeatedly

[D].

any of the above

Answer: Option A

Explanation:

No answer description available for this question.

Question: Column bleeding occurs when
[A].

elution of the analyte is extended over time

[B].

the column is cracked and stationary phase leaks out

[C].

traces of the stationary phase are eluted

[D].

the column breaks during installation and causes personal injury

Answer: Option C

Explanation:

No answer description available for this question.

Question: A retention gap is placed between the injector and the front of the column to
[A].

retain contaminants and prevent them from reaching the column

[B].

retain the sample and release it gradually to the column

[C].

prevent backflush of the injected solution

[D].

all of the above

Answer: Option A

Explanation:

No answer description available for this question.

Question: Helium is generally preferred as carrier gas over nitrogen and hydrogen because
[A].

it is inert

[B].

it has a lower viscosity

[C].

it doubles up as a party gas for balloons and funny voices

[D].

all of above

Answer: Option D

Explanation:

No answer description available for this question.

Question: Doubling the column’s length increases resolution by a factor of
[A].

(2)0.5

[B].

2

[C].

3

[D].

4

Answer: Option A

Explanation:

No answer description available for this question.