Pa
INTRODUCTION
Protactinium (formerly protoactinium) is a radioactive toxic metallic element, and one of the actinide series of the periodic table. Its most stable isotope decays to actinium by emission of an alpha particle.
It is is a member of the uranium-actinium radioactive-decay series and trace amounts are found in uranium ores such as pitchblende.
BASIC INFORMATIONS
- Atomic Number
- 91
- Atomic Mass
- 231.03588
- Ionic radius
- 1.04
- Ionization energy
- N/A
- Electronic config
- 2,8,18,32,20,9,2
- Principal Valency
- +2
- Density g/cm³
- 15.4
- Melting point °C
- 1568
- Boiling point °C
- 4027
- Type of Element
- Metal
- Electronegativity
- N/A
- Element Category
- Actinide series
- Appearance
- Silvery solid
- Block
- f-block
- Period
- 9
- Group
- 6
- No of Isotopes
- 29
- Occurrence
- Radioactive
- Abundance in ppm
- 0.1
- Year of Discovery
- 1917
EXTRACTION
Its precipitate is reduced by barium at 1400'C
OXIDATION STATES
+2,+3,+4,+5, (Weakly basic)
MAJOR SOURCE
Uranium fuel, pitchblende
HALF LIFE
33000 years
ECONOMIC IMPORTANCE
* It is used extensively in research works and no commercial use at present.
