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Gas chromatography method advantages
Another type of chromatography is called gas chromatography. Gas chromatography is an instrumental method of chemical analysis. Scientists tested the orange dyes using gas chromatography.
Suggest two advantages of using the instrumental method of gas chromatography rather than paper chromatography.
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Marking points
- 1 Provides one valid advantage: greater sensitivity/smaller sample, greater accuracy/resolution, or faster analysis.
- 2 Provides a second distinct valid advantage from the official list.
Full-mark answer
1. Gas chromatography is more sensitive, so a smaller sample can be used. 2. It is faster than paper chromatography.
Why this answer loses marks
Gas chromatography is better and more modern.
Neither claim identifies a specific comparative advantage such as sensitivity, accuracy, resolution or speed.