Analytical Chemistry Part 13 Summary PDF

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Summary

INSUMMARY The mobile phase for partition chromatography can also be a gas. Partition chromatography is a type of chromatography in which the stationary phase is a liquid chemically bonded to the surface of a solid substrate, while the mobile phase is either a liquid or gas.  The mixture component...

Description

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The mobile phase for partition chromatography can also be a gas.

the surface of the solid 

Stationary phase -liquid 

IN SUMMARY 

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Partition chromatography is a type of chromatography in which the stationary phase is a liquid chemically bonded to the surface of a solid substrate, while the mobile phase is either a liquid or gas. The mixture components dissolve in and out of the mobile and stationary phases as the mobile phase moves through the stationary phase, and separation occurs as a result Dissolve in and out and then the separation happens when the mobile phase moves through the stationary phase Stationary phase -liquid 

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The separation mechanism is adsorption Adsorption – it is defined as the adhesion of a chemical species onto the surface of particles

Nature of the adsorption – polarity Interaction of polar molecules with a polar stationary phase

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It is a method for separating mixtures of ions, both inorganic and organic. Method for ions The stationary phase consists of very small polymer resin beads that have many ionic bonding sites on their surfaces. These sites selectively exchange ions with certain mobile phase compositions as the mobile phase moves. Ions that bond to the charged site on the resin beads are thus separated from ions that do not bond

ADSORPTION CHROMA- STATIONARY SOLID PHASE The stationary phase consists of finely divided solid particles packed inside a tube, and the mixture components adsorb or stick to

The nature of the adsorption involves the interaction of polar molecules, or molecules with polar groups, with a very polar solid stationary phase. The mobile phase can be either a liquid or a gas

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difference with partition – partition – liquid stationary phase for this solid – the components will adhere into the stationary phase STATIONARY PHASE SOLID

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CONCEPT  

Separation – bonding (affinity with the stationary phase – ability to bond) the beads are charged, compounds having the same charged maybe repelled by the column , meaning they will travel quickly.,

Cation echanger.

ION EXCHANGE FOR DEIONIZATION OF WATER Wide columns packed with a mixture of an anion exchange resin that exchanges dissolved anions for hydroxide ions, and a cation exchange resin that exchanges dissolved cations for hydrogen ions are used because water that is passed through such a column becomes free of ions (deionized) since the hydrogen and hydroxide ions combine to form more water.  Cation exchange chromatography, more specifically, uses a negatively charged ion exchange resin with an affinity for molecules having net positive surface charges. SPECIAL APPLICATION: deionization of water  Hydroxide – negative charge  Hydrogen – positive charge  Combined to form water 

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The stationary phase material can be either an anion exchange resin, which possesses positively charged sites to exchange negative ions, or a cation exchange resin, which possesses negatively charged sites to exchange positive ions. The mobile phase can only be a liquid.

Anion – exchange negative ions (since negative charge) then it possess positive charged sites where the positive ion will be attracted  The two resins: anion and cation resins will exchange cations and anions to produce water

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The Salt is used for the ion...