LANTHANIDE CONTRACTION Meaning and
Definition
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Lanthanide contraction refers to a phenomenon in the periodic table that describes the decrease in atomic and ionic radii of elements as one moves across the lanthanide series from cerium (Ce) to lutetium (Lu). This contraction is caused by the increase in the nuclear charge (number of protons in the nucleus) as one moves across the series.
Due to the lanthanide contraction, the increasing positive charge from the nucleus strongly attracts the outer electrons, resulting in a decrease in atomic radius. This contraction is further accentuated by the filling of the f-orbitals, which are less effective in shielding electrons from the increased charge of the nucleus.
The lanthanide contraction has significant consequences in various chemical and physical properties of lanthanide elements. For example, the decrease in atomic and ionic radii has an impact on the formation of chemical bonds, the solubility and stability of complexes, and the strength of metallic bonds. It also influences the size of coordination complexes and the catalytic activity of lanthanides.
The lanthanide contraction is crucial in understanding the similarities and differences between lanthanide elements and their subsequent behavior in various chemical reactions. It also plays a significant role in the separation and purification techniques of lanthanides, as their similar properties can make isolation challenging.
Common Misspellings for LANTHANIDE CONTRACTION
- Lanthanide contracton
- Lanthade contraction
- Lathanide contraction
- Lathaneide contraction
- Lathanide contration
- Lanthand contraction
- Lanthandide contraction
Etymology of LANTHANIDE CONTRACTION
The term "lanthanide contraction" comes from the combination of two different concepts: "lanthanide" and "contraction".
1. Lanthanide: The word "lanthanide" refers to a series of elements in the periodic table. It is derived from the Greek word "lanthanein", which means "to lie hidden". The term was coined because these elements were initially difficult to separate and identify from one another, hence "hidden". The lanthanide series includes the elements from atomic number 57 (lanthanum, La) to 71 (lutetium, Lu).
2. Contraction: In the context of the lanthanide series, "contraction" refers to a phenomenon observed in these elements. As you move across the lanthanide series, from lanthanum (La) to lutetium (Lu), the atoms gradually decrease in size.
