Extraction of f-block element, Chemistry

Assignment Help:

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.


Related Discussions:- Extraction of f-block element

The number of electrons in the valence shell of calcium, The number of elec...

The number of electrons in the valence shell of calcium is: (1) 6        (2) 8        (3) 2        (4)4 Ans: 2

P- block elements, what are the chemical poperties of p-block elements ?

what are the chemical poperties of p-block elements ?

Explain the term- vacancies, Vacancies  A vacancy is a lattice position...

Vacancies  A vacancy is a lattice position that is vacant due to the atom is missing. It is formed when the solid is formed. Vacancies are simply empty atom site.

Platinichloride method for bases - chemical methods, Platinichloride Method...

Platinichloride Method for Bases - Chemical Methods Organic bases combine along with chloroplatinic acid, H 2 PtCl 6 to make insoluble platinichlorides, that on ignition, opt

Solvent extraction, role of modifiers in solvent extraction of metal ion

role of modifiers in solvent extraction of metal ion

Corresponding eigenvalue. , Show that wavefunction ψ1(x) = (2/L) 1/2 sin(πx...

Show that wavefunction ψ1(x) = (2/L) 1/2 sin(πx/L) of a particle in a box is an eigenfunction of  the operator d 2 /dx 2 and also calculate the corresponding eigenvalue.

Assignment, LITHIUM AND BERYLLIUM MARKEDLY DIFFERENT FROM OTHER MEMBERS OF ...

LITHIUM AND BERYLLIUM MARKEDLY DIFFERENT FROM OTHER MEMBERS OF THEIR RESPECTIVE GROUP?.

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

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!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd