Gas Chromatography MCQ Practice Questions (Bio Chemistry)

Gas chromatography (GC) is a common type of chromatography used in analytical chemistry for separating and analyzing compounds that can be vaporized without decomposition. Typical uses of GC include testing the purity of a particular substance, or separating the different components of a mixture (the relative amounts of such components can also be determined). In some situations, GC may help in identifying a compound. In preparative chromatography, GC can be used to prepare pure compounds from a mixture.

In gas chromatography, the mobile phase (or “moving phase”) is a carrier gas, usually an inert gas such as helium or an unreactive gas such as nitrogen. Helium remains the most commonly used carrier gas in about 90% of instruments although hydrogen is preferred for improved separations. The stationary phase is a microscopic layer of liquid or polymer on an inert solid support, inside a piece of glass or metal tubing called a column (a homage to the fractionating column used in distillation). The instrument used to perform gas chromatography is called a gas chromatograph (or “aerograph”, “gas separator”)

The gaseous compounds being analyzed interact with the walls of the column, which is coated with a stationary phase. This causes each compound to elute at a different time, known as the retention time of the compound. The comparison of retention times is what gives GC its analytical usefulness

These questions will give you basic idea for Examination Preparation and/or interview on Gas chromatography.

Please Note:

1. These questions are only for practice and understanding level of knowledge only. It is not necessary that these questions may or may not appear for examinations and/or interview questions
2. In this practice test, because of large amount of questions (around 26 questions) some of questions may have repeated
3. I had to put as 70% pass rate because there may also be wrong answers from my side