I Apinaya Amuthalingham I BTEC Applied Science I Unit 2 I Coursework I Chemistry I
Learning Aim C I Chromatography I
What is chromatography ?
Chromatography is a method to separate chemical mixtures and to identify substances. You
can find out the purity of the substance. Chromatography can be used to identify if the dye
consists of one substance or a mixture.To conduct chromatography you need moving gas or
liquids over the stationary paper or powder. In chromatography, it depends on the
separation of the substances as they travel between two phases - mobile phase and
stationary phase. Mobile phase is where liquid transports different substance mixtures
through absorption. Stationary phase is where solid materials absorb the mixture flowing
through it. Different substances travel at different speeds in the specified time.
The disadvantages of chromatography is that there will be a problem with the way we
conduct our experiment - especially with our handling techniques. One disadvantage is if our
samples aren’t spotted above the solvent level ; the samples won’t travel with the solvent
before the mobile phase starts; the sample is likely for it to be washed into the solvent.
Another disadvantage is the uneven movement of the solvent in thin - layer chromatography;
using water can negatively cause possible errors .
Paper chromatography is used to separate mixtures of soluble substances. Mostly the
substances are inks, dyes, plant pigments (chlorophyll) or food colouring. The stationary
phase (non - moving) is the paper and the mobile phase is the water based (aqueous)
solvent or carbon based (non - aqueous organic) solvent.
Each chemical substance in a sample has a dynamic equilibrium between the stationary
phase and a mobile phase. Furthermore, separation mainly depends on how the chemicals
are strongly attracted to the mobile and stationary phases of paper chromatography. This
suggests how different samples of chromatograms’ can be compared to different reference
materials.
Thin - layer chromatography is used to analyse the dyes in the fibres, inks and paints. It is
also used to find pesticides or insecticides in food products. It’s similar to paper
chromatography - but instead of stationary paper the stationary phase is an unreactive
substance, (e.g . Silica or Aluminium Oxide), on a supported flat inert surface, (e.g. Glass
Plate).
The advantages of thin - layer chromatography is that the mobile phase moves more quickly
and evenly through the stationary phase. There is also a range of absorption, where atoms,
molecules and ions from a gas or liquid rise to the surface in the stationary phase. Thin-
layer chromatography produces useful chromatograms, showing the produced substance
separation, than paper chromatography. Because it is easier to analyse and compare.
The disadvantages of thin - layer chromatography is where the distance a sample can travel
depends on the size or the polarity of molecules. The polarity of molecules can affect how far
the spots have travelled - depending on what type of solvent we have used. As polar
molecules will be strongly attracted to polar solvents. Therefore, it will move further if polar
solvent is opposed to a non - polar solvent.
1
,Similarities between Thin - Layer Chromatography and Paper Chromatography :-
Similarities
Thin - Layer Chromatography Paper Chromatography
● Same solid stationary phase . ● Same solid stationary phase .
● Same liquid mobile phase . ● Same liquid mobile phase .
● Particle separation is based upon ● Particle separation is based upon
the polarity of the molecules to the the polarity of the molecules to the
stationary and mobile phase . stationary and mobile phase .
● Same solvent jar . ● Same solvent jar .
Differences between Thin - layer Chromatography and Paper Chromatography :-
Differences
Thin - Layer Chromatography Paper Chromatography
● The stationary phase is glass coated ● The stationary phase is water being
with siríaca gel . present in the press of cellulose .
● Requires comparatively little more ● A smaller sample is required .
samples .
● TLC plates can be heated in an ● Chromatography paper cannot be
oven for a longer time . heated in an oven for over a longer
time .
● It is more expensive than paper ● It is cheaper than thin - layer
chromatography . chromatography .
How amino acids are separated by paper and thin - layer chromatography ?
Amino acids can be separated by paper and thin - layer chromatography. Amino acids are
like building blocks of proteins, which are large molecules found in all living things. Proteins
are mainly needed for growth and repair of the body systems. Amino acids can be identified
using the separation of chromatography; but they are colourless compounds. A solution
called ninhydrin is added to produce a purple colour.
What is Chlorophyll ?
Chlorophyll is a green pigment that gives plants a green colour and absorbs light to produce
energy. Chlorophyll helps plants create their own food through the process of
photosynthesis. Chlorophyll’s ability is unique as it enables plants to absorb energy to build
tissues.
Chlorophyll is located in plant’s chloroplasts ; they are tiny structures in plant cells. When
chlorophyll absorbs energy from light it is transferred into two kinds of energy - storing
molecules. Through the process of photosynthesis, plants use the stored energy to convert
carbon dioxide and water into glucose - a type of sugar that respires during photosynthesis
2
, or aerobic respiration in the mitochondria. Plants use glucose altogether, with nutrients taken
from soil to develop new leaves and plant microorganisms. Photosynthesis produces
oxygen; as plants release into the atmosphere.
What is Amino Acids ?
Amino acids are organic compounds that combine to make proteins. Proteins are long
chains of amino acids. Amino acids build muscles and cause chemical reactions in the body.
Our body has thousands of different functions and shapes of proteins. If you combine amino
acids in various ways to make various different protein molecule structures.
Organic chemicals contain carbon and hydrogen bonds. Amino acids have the same basic
structure. Amino acids link together with peptide bonds and become proteins. The forces of
other amino acids.
Amino acids have many important roles in our body. It transports nutrients, boosts our
immune systems, and carries out other functions in the body. But the disadvantages of
amino acids is that it decreases our immunity, digestive problems, fertility issues and many
other health issues.
Rf Value : What it is and How it’s calculated ?
Rf (Retardation factor) value is the ratio of the distance moved by the solute to the distance
moved by the solvent. Rf value is used to compare and identify unknown compounds.
Rf value is a compound that is equal to the distance travelled by the compounds divided by
the distance travelled by the solvent front. Rf values in chromatography is a requirement of
chromatography. Because Rf values tell us if the solute is more related to the stationary or
the mobile phase.
Conclusion : Of Chromatography Methods :-
In conclusion, chromatography is accepted as an effective method to identify separated
mixtures and substances. Paper chromatography helps to identify unknown amino acids and
analyse other relevant mixtures that have properties of being separated by the
chromatography paper. But the most effective method is Thin - Layer Chromatography as it
has more useful chromatograms than Paper Chromatography and shows a greater
separation of components in mixtures. Therefore, it is easier to analyse and compare results
of the distance the spots polarity molecules involved.
3
Learning Aim C I Chromatography I
What is chromatography ?
Chromatography is a method to separate chemical mixtures and to identify substances. You
can find out the purity of the substance. Chromatography can be used to identify if the dye
consists of one substance or a mixture.To conduct chromatography you need moving gas or
liquids over the stationary paper or powder. In chromatography, it depends on the
separation of the substances as they travel between two phases - mobile phase and
stationary phase. Mobile phase is where liquid transports different substance mixtures
through absorption. Stationary phase is where solid materials absorb the mixture flowing
through it. Different substances travel at different speeds in the specified time.
The disadvantages of chromatography is that there will be a problem with the way we
conduct our experiment - especially with our handling techniques. One disadvantage is if our
samples aren’t spotted above the solvent level ; the samples won’t travel with the solvent
before the mobile phase starts; the sample is likely for it to be washed into the solvent.
Another disadvantage is the uneven movement of the solvent in thin - layer chromatography;
using water can negatively cause possible errors .
Paper chromatography is used to separate mixtures of soluble substances. Mostly the
substances are inks, dyes, plant pigments (chlorophyll) or food colouring. The stationary
phase (non - moving) is the paper and the mobile phase is the water based (aqueous)
solvent or carbon based (non - aqueous organic) solvent.
Each chemical substance in a sample has a dynamic equilibrium between the stationary
phase and a mobile phase. Furthermore, separation mainly depends on how the chemicals
are strongly attracted to the mobile and stationary phases of paper chromatography. This
suggests how different samples of chromatograms’ can be compared to different reference
materials.
Thin - layer chromatography is used to analyse the dyes in the fibres, inks and paints. It is
also used to find pesticides or insecticides in food products. It’s similar to paper
chromatography - but instead of stationary paper the stationary phase is an unreactive
substance, (e.g . Silica or Aluminium Oxide), on a supported flat inert surface, (e.g. Glass
Plate).
The advantages of thin - layer chromatography is that the mobile phase moves more quickly
and evenly through the stationary phase. There is also a range of absorption, where atoms,
molecules and ions from a gas or liquid rise to the surface in the stationary phase. Thin-
layer chromatography produces useful chromatograms, showing the produced substance
separation, than paper chromatography. Because it is easier to analyse and compare.
The disadvantages of thin - layer chromatography is where the distance a sample can travel
depends on the size or the polarity of molecules. The polarity of molecules can affect how far
the spots have travelled - depending on what type of solvent we have used. As polar
molecules will be strongly attracted to polar solvents. Therefore, it will move further if polar
solvent is opposed to a non - polar solvent.
1
,Similarities between Thin - Layer Chromatography and Paper Chromatography :-
Similarities
Thin - Layer Chromatography Paper Chromatography
● Same solid stationary phase . ● Same solid stationary phase .
● Same liquid mobile phase . ● Same liquid mobile phase .
● Particle separation is based upon ● Particle separation is based upon
the polarity of the molecules to the the polarity of the molecules to the
stationary and mobile phase . stationary and mobile phase .
● Same solvent jar . ● Same solvent jar .
Differences between Thin - layer Chromatography and Paper Chromatography :-
Differences
Thin - Layer Chromatography Paper Chromatography
● The stationary phase is glass coated ● The stationary phase is water being
with siríaca gel . present in the press of cellulose .
● Requires comparatively little more ● A smaller sample is required .
samples .
● TLC plates can be heated in an ● Chromatography paper cannot be
oven for a longer time . heated in an oven for over a longer
time .
● It is more expensive than paper ● It is cheaper than thin - layer
chromatography . chromatography .
How amino acids are separated by paper and thin - layer chromatography ?
Amino acids can be separated by paper and thin - layer chromatography. Amino acids are
like building blocks of proteins, which are large molecules found in all living things. Proteins
are mainly needed for growth and repair of the body systems. Amino acids can be identified
using the separation of chromatography; but they are colourless compounds. A solution
called ninhydrin is added to produce a purple colour.
What is Chlorophyll ?
Chlorophyll is a green pigment that gives plants a green colour and absorbs light to produce
energy. Chlorophyll helps plants create their own food through the process of
photosynthesis. Chlorophyll’s ability is unique as it enables plants to absorb energy to build
tissues.
Chlorophyll is located in plant’s chloroplasts ; they are tiny structures in plant cells. When
chlorophyll absorbs energy from light it is transferred into two kinds of energy - storing
molecules. Through the process of photosynthesis, plants use the stored energy to convert
carbon dioxide and water into glucose - a type of sugar that respires during photosynthesis
2
, or aerobic respiration in the mitochondria. Plants use glucose altogether, with nutrients taken
from soil to develop new leaves and plant microorganisms. Photosynthesis produces
oxygen; as plants release into the atmosphere.
What is Amino Acids ?
Amino acids are organic compounds that combine to make proteins. Proteins are long
chains of amino acids. Amino acids build muscles and cause chemical reactions in the body.
Our body has thousands of different functions and shapes of proteins. If you combine amino
acids in various ways to make various different protein molecule structures.
Organic chemicals contain carbon and hydrogen bonds. Amino acids have the same basic
structure. Amino acids link together with peptide bonds and become proteins. The forces of
other amino acids.
Amino acids have many important roles in our body. It transports nutrients, boosts our
immune systems, and carries out other functions in the body. But the disadvantages of
amino acids is that it decreases our immunity, digestive problems, fertility issues and many
other health issues.
Rf Value : What it is and How it’s calculated ?
Rf (Retardation factor) value is the ratio of the distance moved by the solute to the distance
moved by the solvent. Rf value is used to compare and identify unknown compounds.
Rf value is a compound that is equal to the distance travelled by the compounds divided by
the distance travelled by the solvent front. Rf values in chromatography is a requirement of
chromatography. Because Rf values tell us if the solute is more related to the stationary or
the mobile phase.
Conclusion : Of Chromatography Methods :-
In conclusion, chromatography is accepted as an effective method to identify separated
mixtures and substances. Paper chromatography helps to identify unknown amino acids and
analyse other relevant mixtures that have properties of being separated by the
chromatography paper. But the most effective method is Thin - Layer Chromatography as it
has more useful chromatograms than Paper Chromatography and shows a greater
separation of components in mixtures. Therefore, it is easier to analyse and compare results
of the distance the spots polarity molecules involved.
3
