ISO general purpose metric screw threads — General planDescripción completa
ISO general purpose metric screw threads — General planFull description
Descripción: n
Full description
Full description
Example assignment for the CIT 261 instruction communication subject.
Clases que he dado.Descripción completa
Descrição completa
Full description
Descripción completa
Splash LatinoFull description
Fastener standardFull description
chem investigatory
Ch 16Full description
chemistry basicsFull description
chemistry practice for chapter 6
Copper chemistryFull description
A2Q for E12 Quantitative Determination of Total Total Ion Concentration by Ion Exchange Chromatography •
Ion exchange chromatography is a chromatographic science concerned ith the separation of various types of charged species in a s ystem! This system is usually comprised of separate phases! This method is founded on the concept of ion exchange beteen to principal sites " the mobile and the stationary phase! In the experiment# resin as used as the stationary phase! $n%non solution is passed through the resin to allo the cation to replace the & '()&* ions bound in the binding sites!
•
+everal factors can affect ion*exchange! These factors include the surface area of the stationary phase ,resin bead si-e.# density of exchange sites on the stationary phase surface ,cross*lin%age.# flo rate of the mobile phase ,resin bead si-e and column geometry/ system pressure in high* pressure chromatography# chromatography# and the chemistry of the mobile phase ,ionic strength of the sample solution# concentration of mobile phase.!
•
The resin as soa%ed in ater for an hour before introducing to the ion*exchange column ,improvised burette. in order to dissolve ater*soluble ater*soluble impurities and ioni-e the functional groups of the resin! 0resence of such impurities can bloc% off sites for exchange hich ill cause a maor problem! Through immersion in ater# the resin as alloed to sell leading to further exposure of the exchange sites! Dry resin cant be used because the exchange sites are still not open!
•
3ater 3a ter level as %ept above the top of the resin to prevent the formation of air poc%ets hich may restrict access of the ions!
•
+trong acid as needed to replace the bound ions in the resin! &ydrogen ion supply as also replenished through the process!
•
It as crucial that the rate flo be maintained at 45 drops per minute to ensure that all copper , II. ions bind to the exchange sites! If the rate is too fast# an incomplete exchange process ill result and less Cu2' ill bind to the sites! If it is too slo# hoever# the process is deemed inefficient due to the increased amount of time needed to complete the procedure!
•
The column as ashed until the eluates p& e6uals that of the distilled ater in order to ma%e sure that the & ' concentration is not affected ith the constant addition of ater in the experiment proper!
•
The balanced reaction for the experiment is7
•
0ossible sources of errors include inade6uate regeneration ith & ' ions hich may result to lesser than actual cation concentration! Incomplete exchange caused by faster flo or the trapped air poc%ets ill also yield loer concentrations! 8ailure to satisfy the p& e6uality at the elution phase ill yield to increase in cation concentration hile failure to satisfy p& e6uality in titration phase ill result to a decrease in cation concentration!
9E8E9E:CE+7 Dudas# 8!)! 2511! Ion Exchange Chromatography!;assachusetts Institute of Technology! oc!mit!edu! 3eb Dyer A!# &udson ;! 8undamentals of Analytical Chemistry# ?th Edition! +aunders College 0ublishing
