What are actinides? (1)
Answers
Answer:
EXAMPLE OF ACTINOIDS - DEFINITION
1. The Actinide series contains elements with atomic numbers 89 to 103 and is the third group in the periodic table.
2. The series is the row below the Lanthanide series, which is located underneath the main body of the periodic table.
3. Actinium, Thorium, uranium curium are the some example of Actinides series.
CHARACTERISTIC OF ACTINOIDS - DEFINITION
1.Occurrence : The first four elements of the series occur's in the earth crust. The remaining are prepared artificially.
2.Colours of ions : Most of the actinoids are coloured .
3.Magnetic property : Many of the actinoid cations exhibit paramagnetic behavior.
ACTINIDE SERIES AND ITS PROPERTIES - DEFINITION
concept
The Actinide are a series of fifteen metal elements with atomic number 89 through 103. The name of the series comes from actinium, the element that marks the beginning of the series. All members of the series have similar chemical properties.
Some of the properties of Actinides are:
Binding energies of 5f electrons are lower
Due to lower binding energies, they show higher oxidation states such as +4, +5 and +6. Ex: Uranium exhibits +6 oxidation state in UF
6
and UO
2
Cl
2
5f electrons have poor shielding effect
Most of their ions are coloured. Ex: U
3+
red, U
4+
green and UO
2
2+
yellow
They have much greater tendency to form complexes
All actinides are radioactive
Their compounds are more basic
They form oxocations. Ex: UO
2
2+
,UO
+
, etc
Elements from Th to Lr are called actinides.