UNIT 2: PRACTICAL SCIENTIFIC PROCEDURES AND TECHNIQUES [40157986 - HAJRAH ALI. MANDEEP MANGAT JUNE 15
C: UNDERTAKE CHROMATOGRAPHIC TECHNIQUES TO IDENTIFY
COMPONENTS IN MIXTURES.
SEPARATE TO IDENTIFY
C.P5 USE CHROMATOGRAPHIC TECHNIQUES TO PRODUCE CHROMATOGRAMS.
[AIM] Our aim is to carry out different chromatographic techniques to separate and identify components in
mixtures. In this assignment we will explain the technique, analyse and evaluate your results and suggest
improvements.
CHROMATOGRAPHY OF AMINO ACIDS
[EQUIPMENT]
Chromatography paper
Amino acid solution
Capillary tube
Solvent (propanol and alcohol)
Ninhydrin
Beaker
Petri dish lid
Pencil (as pen mark will run up)
Ruler
[METHOD]
I. Put a pencil line across the chromatography paper 1cm from the bottom.
II. Place a pencil dot every 1 cm apart for each Amino acid solutions and label them.
III. Use a capillary tube to put amino acid on to the dots. Repeat for all 3 times.
IV. Repeat x4 times
V. Allow the dots to dry
VI. Add solvent to the beaker
VII. Place the chromatography paper into the beaker, ensure that the level of the solvent is below the
line.
VIII. Allow the solvent to rise until it stops. Mark this point with a pencil (solvent front)
IX. Then the technicians will now spray ninhydrin onto the chromatography paper and using a hair
dryer dry the points in a fume cupboard
X. Calculate the Rf (retention factor) value of each amino acid and name it
CHROMATOGRAPHY OF PLANT PIGMENTS
[EQUIPMENT]
TLC plate
Pencil
Ruler
Pestle and mortar
Propane
Watch glass
Capillary tube
Solvent (propanol and alcohol)
, UNIT 2: PRACTICAL SCIENTIFIC PROCEDURES AND TECHNIQUES [40157986 - HAJRAH ALI. MANDEEP MANGAT JUNE 15
Beaker
Petri dish lid
[METHOD]
I. Put a pencil line across the TLC plate 1 cm from the bottom.
II. Place a pencil dot in the middle of the line.
III. Now using a pestle and mortar crush the leaves.
IV. Add few drops of propanone to the green mush and mix.
V. Transfer the dark green liquid into a watch glass
VI. Use a capillary tube to transfer the green extract on to the TLC plate dot, repeat this four times.
VII. Allow the dot to dry.
VIII. Add solvent to the beaker provided.
IX. Place the TLC plate into the beaker ensure that the level of the solvent is below the pencil line.
X. Allow the solvent to rise until it stops. Mark this point with a pencil (solvent front)
XI. Take a picture of your chromatogram as the colours fade quickly.
XII. Calculate the Rf (retention factor) value of each PIGMENT and name them.
[RISK ASSESSMENT]
C.P6 EXPLAIN THE USE OF CHROMATOGRAPHIC TECHNIQUES TO SEPARATE MIXTURES.
PRINCIPLES OF CHROMATOGRAPHY:
Chromatography is a method used to separate coloured chemicals or substances. It has a mobile phase and
a stationary phase which is normally solvent and paper. The mobile phase is the one that carries the
substances as they travel through the stationary phase i.e., liquid or gas. The stationary is the phase that is
stationary i.e., the paper or TLC plate as they do not move. So, the movement of molecules will depend on
these stages e.g., how much it dissolves in the solvent.
PAPER CHROMATOGRAPHY:
Paper chromatography is a basic technique its
Stationary phase: is paper
Mobile phase: propanone (can either be aqueous or non-aqueous organic solvent)
The preparation of the sample is simple and is good for separating water soluble inks. This is because there
is a limit of the different types of solvent, we can used for the mobile phase which limits what can be
separated. It can be time consuming as it is slow and can see the results by the naked eye or UV light. The
advantages of paper chromatography can separate water-soluble compounds such as inks, and can detect
the results by the naked eye, its disadvantages is that it cab be prone to smearing and is limited types of
mobile phases can be used.
Substances are separated as they travel in a mobile phase which passes over a stationary phase. The
substances travel at different speeds, so some move further than others in the time specified. Factors that
affect the separation can depend on how strongly attracted the chemicals are to the mobile and the
stationary phase, the size of the paper larger surface area. This is unique to each chemical compound. The
paper has a thin coating of water molecules which can affect the results of the Substances due to the
manufacturing process and the cellulose fibres which is how the paper is produced, absorb moisture from
the air. The type of solvent also affects the rate of separation because it needs to be soluble. The distance
travelled can depend on the size of molecule or polarity.
C: UNDERTAKE CHROMATOGRAPHIC TECHNIQUES TO IDENTIFY
COMPONENTS IN MIXTURES.
SEPARATE TO IDENTIFY
C.P5 USE CHROMATOGRAPHIC TECHNIQUES TO PRODUCE CHROMATOGRAMS.
[AIM] Our aim is to carry out different chromatographic techniques to separate and identify components in
mixtures. In this assignment we will explain the technique, analyse and evaluate your results and suggest
improvements.
CHROMATOGRAPHY OF AMINO ACIDS
[EQUIPMENT]
Chromatography paper
Amino acid solution
Capillary tube
Solvent (propanol and alcohol)
Ninhydrin
Beaker
Petri dish lid
Pencil (as pen mark will run up)
Ruler
[METHOD]
I. Put a pencil line across the chromatography paper 1cm from the bottom.
II. Place a pencil dot every 1 cm apart for each Amino acid solutions and label them.
III. Use a capillary tube to put amino acid on to the dots. Repeat for all 3 times.
IV. Repeat x4 times
V. Allow the dots to dry
VI. Add solvent to the beaker
VII. Place the chromatography paper into the beaker, ensure that the level of the solvent is below the
line.
VIII. Allow the solvent to rise until it stops. Mark this point with a pencil (solvent front)
IX. Then the technicians will now spray ninhydrin onto the chromatography paper and using a hair
dryer dry the points in a fume cupboard
X. Calculate the Rf (retention factor) value of each amino acid and name it
CHROMATOGRAPHY OF PLANT PIGMENTS
[EQUIPMENT]
TLC plate
Pencil
Ruler
Pestle and mortar
Propane
Watch glass
Capillary tube
Solvent (propanol and alcohol)
, UNIT 2: PRACTICAL SCIENTIFIC PROCEDURES AND TECHNIQUES [40157986 - HAJRAH ALI. MANDEEP MANGAT JUNE 15
Beaker
Petri dish lid
[METHOD]
I. Put a pencil line across the TLC plate 1 cm from the bottom.
II. Place a pencil dot in the middle of the line.
III. Now using a pestle and mortar crush the leaves.
IV. Add few drops of propanone to the green mush and mix.
V. Transfer the dark green liquid into a watch glass
VI. Use a capillary tube to transfer the green extract on to the TLC plate dot, repeat this four times.
VII. Allow the dot to dry.
VIII. Add solvent to the beaker provided.
IX. Place the TLC plate into the beaker ensure that the level of the solvent is below the pencil line.
X. Allow the solvent to rise until it stops. Mark this point with a pencil (solvent front)
XI. Take a picture of your chromatogram as the colours fade quickly.
XII. Calculate the Rf (retention factor) value of each PIGMENT and name them.
[RISK ASSESSMENT]
C.P6 EXPLAIN THE USE OF CHROMATOGRAPHIC TECHNIQUES TO SEPARATE MIXTURES.
PRINCIPLES OF CHROMATOGRAPHY:
Chromatography is a method used to separate coloured chemicals or substances. It has a mobile phase and
a stationary phase which is normally solvent and paper. The mobile phase is the one that carries the
substances as they travel through the stationary phase i.e., liquid or gas. The stationary is the phase that is
stationary i.e., the paper or TLC plate as they do not move. So, the movement of molecules will depend on
these stages e.g., how much it dissolves in the solvent.
PAPER CHROMATOGRAPHY:
Paper chromatography is a basic technique its
Stationary phase: is paper
Mobile phase: propanone (can either be aqueous or non-aqueous organic solvent)
The preparation of the sample is simple and is good for separating water soluble inks. This is because there
is a limit of the different types of solvent, we can used for the mobile phase which limits what can be
separated. It can be time consuming as it is slow and can see the results by the naked eye or UV light. The
advantages of paper chromatography can separate water-soluble compounds such as inks, and can detect
the results by the naked eye, its disadvantages is that it cab be prone to smearing and is limited types of
mobile phases can be used.
Substances are separated as they travel in a mobile phase which passes over a stationary phase. The
substances travel at different speeds, so some move further than others in the time specified. Factors that
affect the separation can depend on how strongly attracted the chemicals are to the mobile and the
stationary phase, the size of the paper larger surface area. This is unique to each chemical compound. The
paper has a thin coating of water molecules which can affect the results of the Substances due to the
manufacturing process and the cellulose fibres which is how the paper is produced, absorb moisture from
the air. The type of solvent also affects the rate of separation because it needs to be soluble. The distance
travelled can depend on the size of molecule or polarity.
