Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
Q. Extraction of f-block element ?
As all the lanthanides occur together in nature, their extraction involves two main steps: (i) separation from one another and (ii) reduction of their compounds to metals. Since the lanthanides are all typically trivalent and are almost identical in size, their chemical properties ark almost similar. Thus, the separation of lanthanides from one another is a very difficult task, almost as difficult as the separation of isotopes. Only europium and cerium will be separated from the remaining lanthanides by employing conventional Q+ chemical methods because of stabilities of Ce 4+and EU2+ in aqueous solution. Cerium can be separated from a mixture of lanthanides by oxidising ce3+ to ce4+ with permanganate or bromate or hypochlorite in an alkaline medium and subsequently precipitating it as Ce02. Europium can be reduced to EU2+ either by electrolytic reduction with a mercury cathode or by using zinc amalgam. It is then precipitated from the solution as EuSo4.
Earlier the lanthanides used to be separated from each other by selective precipitation or by fractional crystallisation. With a limited amount of a precipitating agent, the substance uhichis least soluble is precipitated first. For example, if a base is added to a solution of lanthanide nitrates, the least soluble Lu(OH)3 is precipitated first and the most soluble - La(OH)3 last. As only a partial separation is effected, the precipitate is redissolved and the method is repeated several times.
a sample of CaCo3 and MgCo3 weighing 192g is ignited to constanr weight of 104 gm . what is the composition of mixture ?
the name of the group of metals that easily loses electrons
curd formation in soya milk
how can we identify the ammonical smell and punjent smell?
Schiff's reaction and Tischenko reaction (a) Schiff's reaction: this reaction restores pink colour to Schiff's reagent (aqueous solution of p-rosaniline hydrochloride decolouri
Uses of Catechol Catechol finds use as photographic developer and in the manufacture of alizarin and adrenaline hormone and like an antioxidant (inhibitor in auto oxidation) fo
Penta valent element has one electron more than 4 electrons which could be used for conduction while the trivalent elements has 1 electron less , this can also be seen as a hole
analysis of group III basic radicals Ti 4+, Th4+, Zr4+, V5+, Ce4+ and UO2 2+
#question.synthesis , postad date 1/12/2013, australia
why halogens are both +R and -I groups?
Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd