اطلاعات پایه ای در مورد لانتانیدها

Name: Lanthanum
Symbol: La
Atomic Number: 57
Atomic Mass: 138.9055 amu
Melting Point: 920.0 °C (1193.15 K, 1688.0 °F)
Boiling Point: 3469.0 °C (3742.15 K, 6276.2 °F)
Number of Protons/Electrons: 57
Number of Neutrons: 82
Classification: Rare Earth
Crystal Structure: Hexagonal
Density @ 293 K: 6.7 g/cm³
Color: white

 

 

Atomic Structure

Number of Energy Levels: 6   First Energy Level: 2 Second Energy Level: 8 Third Energy Level: 18 Fourth Energy Level: 18 Fifth Energy Level: 9 Sixth Energy Level: 2

 

Isotopes

Isotope	Half Life
La-134	6.5 minutes
La-137	6000.0 years
La-138	1.05E10 years
La-139	Stable
La-140	1.67 days
La-141	3.9 hours
La-142	1.54 minutes

 

Facts

Date of Discovery: 1839
Discoverer: Carl Mosander
Name Origin: From the Greek word lanthaneis (to lie hidden)
Uses: expensive camera lenses
Obtained From: monazite, bastnasite

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