C2.1.6 - Chromatography Flashcards Preview

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Flashcards in C2.1.6 - Chromatography Deck (22)
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1

How many chemical phases are in chromatography?

2

2

What are the chemical phases in chromatography called?

Stationary and mobile

3

What is the difference between a stationary and mobile phase?

Stationary - cannot move
Mobile - can move

4

What is the stationary phase in paper chromatography?

Absorbent paper

5

What is the mobile phase in paper chromatography?

Any solvent

6

What is the stationary phase of thin-layer chromatography?

A thin layer of silica or alumina powder spread over a plate of glass or plastic

7

What are paper and thin-layer chromatography used for?

Separating soluble coloured substances

8

Explain the process of thin-layer chromatography?

Put the solvent into a chromatography tank to a depth of about 1cm. Add a small amount of sample, taking care not to damage the powder on the plate. Let the solvent travel through the powder, and take the plate out before it reaches the top. Analyse the pattern of coloured spots

9

What is a chromatogram?

The graph that is created to analyse the results

10

What is the chromatography tank used for?

To place the substances in to start chromatography

11

What does the pattern produced in chromatography depend on?

How each component was distributed during each of the chemical phase

12

What would happen if the component forms a stronger bond with the mobile phase than the stationary phase?

It moves further up the plate

13

What happens if the component creates a stronger bond with the stationary phase than the mobile phase?

The component doesn’t move very far up the plate

14

What is the stationary phase in gas chromatography?

Silica or alumina powder packed into a metal column

15

What is the mobile phase in gas chromatography?

An unreactive carrier gas

16

What does gas chromatography do?

Separates the components of a mixture and also measure their amounts

17

Name all the equipment used in gas chromatography

Vent
Flow meter
Carrier gas cylinder and carrier gas
Oven
Detector
Chromatography
Column

18

What does the carrier gas cylinder do?

Supply the mobile phase

19

Where is the metal column located in during gas chromatography?

In between

20

What does the detector do?

Sends a signal to the computer every time a new component leaves the column

21

Where is the metal column detected?

In the oven

22

How do you calculate the Rt value?

Distance travelled by substance
————————————————-
Distance travelled by solvent

They vary from 0 to 1