--%>
Assignment Help - homework help

  Lanthanide Series

The Lanthanide Series:

The Lanthanide series comprise fifteen elements that is, lanthanum (57La) to lutetium (71 Lu). Lanthanum and Lutetium contain no partly filled 4f-subshell however contains electrons in 5d-subshell. Therefore such elements must not be involved in this series. Though, all these elements intimately resemble lanthanum and therefore are considered altogether.

General properties of Lanthanides:

1. Electronic configuration:

The electronic configuration of Lanthanides is listed in the table shown below. The fourteen electrons are filled in Ce to Lu through configuration [54Xe] 4f1-145d16s2

2. Oxidation states:

The general oxidation state displayed by all the lanthanides is +3 (Ln3+) in aqueous solutions and in their solid compounds. Several elements display +2 and +4 states as unusual oxidation states.

La         - +3
Ce         - +3, +4, +2
Pr          - +3, +4
Nd         - +3, +4, +2

3. Radii of tripositive lanthanide ions:

The size of M3+ ions reduces as we move via the lanthanides from lanthanum to lutetium. This steady reduction in ionic radii of M3+ cations in the lanthanide sequence is termed as Lanthanide contraction.

Cause of lanthanide contraction:

The lanthanide contraction is due to the deficient shielding of one 4f electron by the other in similar sub shell. As we move all along the lanthanide sequence, the nuclear charge and the number of 4f electrons raise by one unit at each step.

Though, due to the imperfect shielding, efficient nuclear charge raises causing a contraction in electron cloud of 4f-subshell.

 

Latest technology based Chemistry Online Tutoring Assistance

Tutors, at the www.tutorsglobe.com, take pledge to provide full satisfaction and assurance in F Block Elements homework help via online tutoring. Students are getting 100% satisfaction by online tutors across the globe. Here you can get homework help for F Block Elements, project ideas and tutorials. We provide email based F Block Elements homework help. You can join us to ask queries 24x7 with live, experienced and qualified online tutors specialized in F Block Elements. Through Online Tutoring, you would be able to complete your homework or assignments at your home. Tutors at the TutorsGlobe are committed to provide the best quality online tutoring assistance for Inorganic-Chemistry Homework Help and assignment help services. They use their experience, as they have solved thousands of the Chemistry assignments, which may help you to solve your complex issues of F Block Elements. TutorsGlobe assure for the best quality compliance to your homework. Compromise with quality is not in our dictionary. If we feel that we are not able to provide the homework help as per the deadline or given instruction by the student, we refund the money of the student without any delay.