Inorganic Chemistry> What is lanthanide contraction?...

What is lanthanide contraction?

sathish b , 9 Years ago

Grade 12

9 Answers

Boss

Last Activity: 9 Years ago

Lanthanoid contraction, also called lanthanide contraction, in chemistry, the steady decrease in the size of the atoms and ions of the rare earth elements with increasing atomic number from lanthanum (atomic number 57) through lutetium (atomic number 71). For each consecutive atom the nuclear charge is more positive by one unit, accompanied by a corresponding increase in the number of electrons present in the 4f orbitals surrounding the nucleus. The 4f electrons very imperfectly shield each other from the increased positive charge of the nucleus, so that the effective nuclear charge attracting each electron steadily increases through the lanthanoid elements, resulting ... (100 of 235 words)

PRAPULPODISHETTI

Last Activity: 9 Years ago

The gradual decrease in the atomic and ionic sizes of lanthanides with increase in atomic number due to poor shielding effect of 4f-orbitals is called lanthanide contraction Consequences of lanthanide contraction

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KUNCHAM SAMPATH

Last Activity: 9 Years ago

Lanthanide contraction is a term used in chemistry to describe the greater-than-expected decrease in ionic radii of the elements in the lanthanide series from atomic number 57, lanthanum, to 71, lutetium, which results in smaller than otherwise expected ionic radii for the subsequent elements starting with 72, hafnium.^[1]^[2]^[3] The term was coined by the Norwegian geochemist Victor Goldschmidt in his series "Geochemische Verteilungsgesetze der Elemente".^[4]

Element	La	Ce	Pr	Nd	Pm	Sm	Eu	Gd	Tb	Dy	Ho	Er	Tm	Yb	Lu
Atomic electron configuration (all begin with [Xe])	5d¹6s²	4f¹5d¹6s²	4f³6s²	4f⁴6s²	4f⁵6s²	4f⁶6s²	4f⁷6s²	4f⁷5d¹6s²	4f⁹6s²	4f¹⁰6s²	4f¹¹6s²	4f¹²6s²	4f¹³6s²	4f¹⁴6s²	4f¹⁴5d¹6s²
Ln³⁺ electron configuration	4f⁰	4f¹	4f²	4f³	4f⁴	4f⁵	4f⁶	4f⁷	4f⁸	4f⁹	4f¹⁰	4f¹¹	4f¹²	4f¹³	4f¹⁴
Ln³⁺ radius (pm) (6-coordinate)	103	102	99	98.3	97	95.8	94.7	93.8	92.3	91.2	90.1	89	88	86.8	86.1

SHANMUKESHWAR

Last Activity: 9 Years ago

Lanthanide contraction is a term used in chemistry to describe the greater-than-expected decrease in ionic radii of the elements in the lanthanide series from atomic number 57, lanthanum, to 71, lutetium, which results in smaller than otherwise expected ionic radii for the subsequent elements starting with 72, hafnium.

santhosh

Last Activity: 9 Years ago

venky

Last Activity: 9 Years ago

SAIMANIKANTA

Last Activity: 9 Years ago

pa1

Last Activity: 9 Years ago

Element	La	Ce	Pr	Nd	Pm	Sm	Eu	Gd	Tb	Dy	Ho	Er	Tm	Yb	Lu
Atomic electron configuration (all begin with [Xe])	5d¹6s²	4f¹5d¹6s²	4f³6s²	4f⁴6s²	4f⁵6s²	4f⁶6s²	4f⁷6s²	4f⁷5d¹6s²	4f⁹6s²	4f¹⁰6s²	4f¹¹6s²	4f¹²6s²	4f¹³6s²	4f¹⁴6s²	4f¹⁴5d¹6s²
Ln³⁺ electron configuration	4f⁰	4f¹	4f²	4f³	4f⁴	4f⁵	4f⁶	4f⁷	4f⁸	4f⁹	4f¹⁰	4f¹¹	4f¹²	4f¹³	4f¹⁴
Ln³⁺ radius (pm) (6-coordinate)	103	102	99	98.3	97	95.8	94.7	93.8	92.3	91.2	90.1	89	88

E.Nandhini ketha

Last Activity: 7 Years ago

The lanthanide contraction is greater than expected decrease in ionic radii of the elements in the lanthanide series from atomic number 57, lanthanum, to 71, lutetium, which results in smaller than otherwise expected ionic radii for the subsequent elements starting with 72, hafnium.