I have many sources for my study but with different column features. I mean column diameter etc features doesn't match. So how can i set the method parameters?
"True" temperature and pressure ?
Please contact someone at your school who is in charge of and experienced in using GC as an analytical technique. Training is required to both use the instrument AND to develop or run an analysis method. It takes many years of professional training to be profiecient at GC. Do you desire to spend several years learning this OR would you just like to use the technique to solve a homework or study question at school. To use the technique to solve a problem, please obtain local help from your school's department. A web forum like this one is a poor tool to assist someone just starting out.
*Column choice is determined by application.
**Once the column and method are described, column back pressure (gas flow) can be adjusted relative to the column size (ID) to obtain a linear flow rate.
In each software you use to set up your chromatography settings temperature should be customizable and you should have information regarding pressure at specific flow rate...
The choice of chromatographic conditions depends solely on the sample you analyze. The temperature (temperature range) is determined by the boiling point of the analyzed sample, while the pressure is selected taking into account the length and internal diameter of the column to ensure the desired flow rate of the carrier gas. In the case of GCMS, the flow rate should not be too high so that the pressure in the ion source does not exceed the critical value indicated in the manual for the device.
True temperature: you can check the temperature with a thermocouple or a thermometer (one with an adequate scale, please), although these instruments must be calibrated as well. I wouldn't check pressure; I would rather check the flow with a bubble meter. The flow should correspond to the pressure if I fed the GC computer program that controls the instrument with the correct column dimensions in length, internal diameter and the nature of the mobile phase gas. If the column is not new - and sometimes even if it is new - you should also check the length of the column by counting the number of laps and multiplying them by 2 x pi x r. However, you should never do anything like this without first consulting the instrument manual or checking with the people that worked with the instrument before. You can also consult the vendor and the company that provided the instrument as well, after consulting your own crew.
Ademario: I think you misunderstood the question being asked. The original poster did not mean literally how to check the temperature (for calibration or PV purposes). They have no experience using or working with GC and are inquiring how they go about figuring out what temperature, flow and backpressures are used (They have no idea that their question is unanswerable). This is a training issue.
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