Gas chromatography is a separation technique that uses the differences in how compounds partition between a mobile gas phase and a stationary liquid phase. It works by injecting a sample mixture into a column, where each component interacts differently with the stationary phase and moves through the column at different rates, allowing separation. Key components are the carrier gas, injection port, column, oven, and detector. Factors like temperature, carrier gas flow rate, and column length affect separation by impacting how long each component is retained in the column.

2. OUTLINES
 CHROMATOGRAPHY
 HISTORY
 GAS CHROMATOGRAPHY
 GAS CHROMATOGRAPH MAIN
COMPONENTS
 WORKING PRINCIPLE OF GC
 PROCEDURE OF GC
 FACTORS AFFECTING GC

3. •Greek word “CHROMA” and
“Graphein”.
•Process of separation and
analyzation of complex mixture

4. It works on the basis of rate at
which the types of components
flow. As the mixture of various
components enter the
chromatograph we will observe
that the different components
of a mixture move/flow at
different rate. This different
rate of flowing is responsible for

6. Mikhail Tswett
Russian Botanist
(1872-1919)
John Martin
British chemist
1910-2002

7.  Gas chromatography is separation
method.
Gas chromatography is
a chromatographic technique that can
be used to separate volatile organic
compounds.
Gas Chromatography consists of
two phases.
 Mobile Phase
 Stationary phase

9. GAS CHROMATOGRAPH MAIN
COMPONENETS:
Carrier Gas
Injection Port
Column
Oven
Detector
Sample

11.  This is the mobile phase and
should be inert gas(he, ar etc)
INJECTION PORT
 The injection port consist of
rubber septum through which a
syringe needle is inserted to
inject the sample.

12. COLUMN
Column is the most important
component where separation takes
place.
OVEN
Oven is also an important
component in which column is
fitted.

13. DETECTOR
Detector is to indicate the
presence and measure the amount
of component eluted out from the
column.
SAMPLE
The mixture of components
which is to be analyzed.

14. WORKING PRINCIPLE OF
GC
 It works on the principle that the
organic compounds are separated due
to differences in their partitioning
behavior between Mobile phase and
Stationary phase.
 The mobile phase is comprised of
inert gas.
The stationary phase consists of
packed column.

15. PROCEDURE OF
GC Sample is injected in column.
 Oven heats the system to
vaporize the sample and speed
its passage through the column.
 The different components of
the sample will be separated by
the column because each of the
components “sticks” to the liquid
coating that on the column
packing differently.

16.  When a substance leaves the
column, it is sensed by a detector.
 The detector generates the
voltage that is proportional to the
amount of the substance.
 Chromatogram

18. Temperature: T he higher the
temperature, the more of the
compound is in the gas phase.
Carrier gas flow: If the carrier
gas flow is high, the molecules do not
have a chance to interact with the
stationary phase.
 Column length: The longer the
column is the better the separation
usually is.

19. Amount of material injected: The
injection of too much sample causes
poor separation.
Conclusion: High temperatures and
high flow rates decrease the retention
time, but also deteriorate the quality of
the separation.

20. PRESENTED BY:
ALLAH WARAYO
(12PG41)
NOOR MUHAMMAD
(12PG37)
ABDUL KARIM
(12PG34)

21. Question or any Queries