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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Name: Cerium
Symbol: Ce
Atomic Number: 58
Atomic Mass: 140.116 amu
Melting Point: 795.0 °C (1068.15 K, 1463.0 °F)
Boiling Point: 3257.0 °C (3530.15 K, 5894.6 °F)
Number of Protons/Electrons: 58
Number of Neutrons: 82
Classification: Rare Earth
Crystal Structure: Cubic
Density @ 293 K: 6.773 g/cm³
Color: gray

 

 

Atomic Structure

Number of Energy Levels: 6   First Energy Level: 2 Second Energy Level: 8 Third Energy Level: 18 Fourth Energy Level: 20 Fifth Energy Level: 8 Sixth Energy Level: 2

 

Isotopes

Isotope	Half Life
Ce-134	3016.0 days
Ce-136	Stable
Ce-138	Stable
Ce-139	137.6 days
Ce-140	Stable
Ce-141	32.5 days
Ce-142	Stable
Ce-143	1.4 days
Ce-144	284.6 days

 

Facts

Date of Discovery: 1803
Discoverer: W. von Hisinger
Name Origin: Ceres (asteroid)
Uses: heat-resistant alloys
Obtained From: monazite

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Name: Praseodymium
Symbol: Pr
Atomic Number: 59
Atomic Mass: 140.90765 amu
Melting Point: 935.0 °C (1208.15 K, 1715.0 °F)
Boiling Point: 3127.0 °C (3400.15 K, 5660.6 °F)
Number of Protons/Electrons: 59
Number of Neutrons: 82
Classification: Rare Earth
Crystal Structure: Hexagonal
Density @ 293 K: 6.77 g/cm³
Color: Unknown

 

 

Atomic Structure

Number of Energy Levels: 6   First Energy Level: 2 Second Energy Level: 8 Third Energy Level: 18 Fourth Energy Level: 21 Fifth Energy Level: 8 Sixth Energy Level: 2

 

Isotopes

Isotope	Half Life
Pr-141	Stable
Pr-142	19.12 hours
Pr-143	13.57 days
Pr-144	17.28 minutes
Pr-145	7.2 minutes

 

Facts

Date of Discovery: 1885
Discoverer: C.F. Aver von Welsbach
Name Origin: From the Greek words prasios (green) and didymos (twin)
Uses: coloring glass and ceramics
Obtained From: salts

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Name: Neodymium
Symbol: Nd
Atomic Number: 60
Atomic Mass: 144.24 amu
Melting Point: 1010.0 °C (1283.15 K, 1850.0 °F)
Boiling Point: 3127.0 °C (3400.15 K, 5660.6 °F)
Number of Protons/Electrons: 60
Number of Neutrons: 84
Classification: Rare Earth
Crystal Structure: Hexagonal
Density @ 293 K: 7.007 g/cm³
Color: silvery

 

 

Atomic Structure

Number of Energy Levels: 6   First Energy Level: 2 Second Energy Level: 8 Third Energy Level: 18 Fourth Energy Level: 22 Fifth Energy Level: 8 Sixth Energy Level: 2

 

Isotopes

Isotope	Half Life
Nd-142	Stable
Nd-143	Stable
Nd-144	2.1E15 years
Nd-145	Stable
Nd-146	Stable
Nd-147	10.98 days
Nd-148	Stable
Nd-149	1.72 hours
Nd-150	Stable

 

Facts

Date of Discovery: 1925
Discoverer: C.F. Aver von Welsbach
Name Origin: From the Greek words neos (new) and didymos (twin)
Uses: coloring glass and ceramics, infrared radiation filtering
Obtained From: electrolysis of salts

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Name: Promethium
Symbol: Pm
Atomic Number: 61
Atomic Mass: (145.0) amu
Melting Point: Unknown
Boiling Point: Unknown
Number of Protons/Electrons: 61
Number of Neutrons: 84
Classification: Rare Earth
Crystal Structure: Hexagonal
Density @ 293 K: 6.475 g/cm³
Color: Unknown

 

 

Atomic Structure

Number of Energy Levels: 6   First Energy Level: 2 Second Energy Level: 8 Third Energy Level: 18 Fourth Energy Level: 23 Fifth Energy Level: 8 Sixth Energy Level: 2

 

Isotopes

Isotope	Half Life
Pm-143	265.0 years
Pm-144	360.0 years
Pm-145	17.7 years
Pm-146	5.53 years
Pm-147	2.62 years
Pm-148	5.37 days
Pm-148m	41.3 days
Pm-149	2.21 days
Pm-151	1.18 days

 

Facts

Date of Discovery: 1945
Discoverer: J.A. Marinsky
Name Origin: From the god Prometheus (who stole fire of the sky and gave it to man)
Uses: No uses known
Obtained From: fission products of uranium, thorium, plutonium

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Name: Samarium
Symbol: Sm
Atomic Number: 62
Atomic Mass: 150.36 amu
Melting Point: 1072.0 °C (1345.15 K, 1961.6 °F)
Boiling Point: 1900.0 °C (2173.15 K, 3452.0 °F)
Number of Protons/Electrons: 62
Number of Neutrons: 88
Classification: Rare Earth
Crystal Structure: Rhombohedral
Density @ 293 K: 7.54 g/cm³
Color: silver

 

 

Atomic Structure

Number of Energy Levels: 6   First Energy Level: 2 Second Energy Level: 8 Third Energy Level: 18 Fourth Energy Level: 24 Fifth Energy Level: 8 Sixth Energy Level: 2

 

Isotopes

Isotope	Half Life
Sm-144	Stable
Sm-145	340.0 days
Sm-146	1.03E8 years
Sm-147	1.06E11 years
Sm-148	7.0E15 years
Sm-149	Stable
Sm-150	Stable
Sm-151	90.0 years
Sm-152	Stable
Sm-153	1.92 days
Sm-154	Stable

 

Facts

Date of Discovery: 1879
Discoverer: Paul Emile Lecoq de Boisbaudran
Name Origin: smarskite (mineral)
Uses: used in magnets, in alloys with cobalt, and nuclear reactors
Obtained From: found with other rare earths

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Name: Europium
Symbol: Eu
Atomic Number: 63
Atomic Mass: 151.964 amu
Melting Point: 822.0 °C (1095.15 K, 1511.6 °F)
Boiling Point: 1597.0 °C (1870.15 K, 2906.6 °F)
Number of Protons/Electrons: 63
Number of Neutrons: 89
Classification: Rare Earth
Crystal Structure: Cubic
Density @ 293 K: 5.259 g/cm³
Color: silver

 

 

Atomic Structure

Number of Energy Levels: 6   First Energy Level: 2 Second Energy Level: 8 Third Energy Level: 18 Fourth Energy Level: 25 Fifth Energy Level: 8 Sixth Energy Level: 2

 

Isotopes

Isotope	Half Life
Eu-147	24.4 days
Eu-148	54.5 days
Eu-149	93.1 days
Eu-150	36.0 years
Eu-151	Stable
Eu-152	13.5 years
Eu-152m	9.3 hours
Eu-153	Stable
Eu-154	8.6 years
Eu-155	7.4 years
Eu-156	15.2 days

 

Facts

Date of Discovery: 1901
Discoverer: Eugene Demarcay
Name Origin: Europe
Uses: color televisions
Obtained From: Man-made

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Name: Gadolinium
Symbol: Gd
Atomic Number: 64
Atomic Mass: 157.25 amu
Melting Point: 1311.0 °C (1584.15 K, 2391.8 °F)
Boiling Point: 3233.0 °C (3506.15 K, 5851.4 °F)
Number of Protons/Electrons: 64
Number of Neutrons: 93
Classification: Rare Earth
Crystal Structure: Hexagonal
Density @ 293 K: 7.895 g/cm³
Color: Silverish

 

 

Atomic Structure

Number of Energy Levels: 6   First Energy Level: 2 Second Energy Level: 8 Third Energy Level: 18 Fourth Energy Level: 25 Fifth Energy Level: 9 Sixth Energy Level: 2

 

Isotopes

Isotope	Half Life
Gd-148	75.0 years
Gd-150	1800000.0 years
Gd-151	124.0 days
Gd-152	1.1E11 years
Gd-153	241.6 days
Gd-154	Stable
Gd-155	Stable
Gd-156	Stable
Gd-157	Stable
Gd-158	Stable
Gd-159	18.6 hours
Gd-160	Stable
Gd-162	8.4 minutes

 

Facts

Date of Discovery: 1880
Discoverer: Jean de Marignac
Name Origin: gadolinite (mineral)
Uses: magnetic
Obtained From: gadolinite

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Name: Terbium
Symbol: Tb
Atomic Number: 65
Atomic Mass: 158.92534 amu
Melting Point: 1360.0 °C (1633.15 K, 2480.0 °F)
Boiling Point: 3041.0 °C (3314.15 K, 5505.8 °F)
Number of Protons/Electrons: 65
Number of Neutrons: 94
Classification: Rare Earth
Crystal Structure: Hexagonal
Density @ 293 K: 8.27 g/cm³
Color: silverish

 

 

Atomic Structure

Number of Energy Levels: 6   First Energy Level: 2 Second Energy Level: 8 Third Energy Level: 18 Fourth Energy Level: 27 Fifth Energy Level: 8 Sixth Energy Level: 2

 

Isotopes

Isotope	Half Life
Tb-151	17.61 hours
Tb-155	5.3 days
Tb-156	5.3 days
Tb-157	110.0 years
Tb-158	180.0 years
Tb-159	Stable
Tb-160	72.3 days
Tb-161	6.91 days
Tb-162	7.6 minutes

 

Facts

Date of Discovery: 1843
Discoverer: Carl Mosander
Name Origin: Ytterby (a town in Sweden)
Uses: in color TV's
Obtained From: with other rare earths

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Name: Dysprosium
Symbol: Dy
Atomic Number: 66
Atomic Mass: 162.5 amu
Melting Point: 1412.0 °C (1685.15 K, 2573.6 °F)
Boiling Point: 2562.0 °C (2835.15 K, 4643.6 °F)
Number of Protons/Electrons: 66
Number of Neutrons: 97
Classification: Rare Earth
Crystal Structure: Hexagonal
Density @ 293 K: 8.536 g/cm³
Color: Unknown

 

 

Atomic Structure

Number of Energy Levels: 6   First Energy Level: 2 Second Energy Level: 8 Third Energy Level: 18 Fourth Energy Level: 28 Fifth Energy Level: 8 Sixth Energy Level: 2

 

Isotopes

Isotope	Half Life
Dy-154	3000000.0 years
Dy-156	Stable
Dy-157	8.1 hours
Dy-158	Stable
Dy-159	144.4 days
Dy-160	Stable
Dy-161	Stable
Dy-162	Stable
Dy-163	Stable
Dy-164	Stable
Dy-165	2.3 hours
Dy-166	3.4 days

 

Facts

Date of Discovery: 1886
Discoverer: Paul Emile Lecoq de Boisbaudran
Name Origin: From the Greek word dysprositos (hard to get at)
Uses: nuclear reactors
Obtained From: erbium, holmium

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Name: Holmium
Symbol: Ho
Atomic Number: 67
Atomic Mass: 164.93031 amu
Melting Point: 1470.0 °C (1743.15 K, 2678.0 °F)
Boiling Point: 2720.0 °C (2993.15 K, 4928.0 °F)
Number of Protons/Electrons: 67
Number of Neutrons: 98
Classification: Rare Earth
Crystal Structure: Hexagonal
Density @ 293 K: 8.54 g/cm³
Color: Silver

 

 

Atomic Structure

Number of Energy Levels: 6   First Energy Level: 2 Second Energy Level: 8 Third Energy Level: 18 Fourth Energy Level: 29 Fifth Energy Level: 8 Sixth Energy Level: 2

 

Isotopes

Isotope	Half Life
Ho-163	4570.0 years
Ho-165	Stable
Ho-166	1.1 days
Ho-166m	1200.0 years

 

Facts

Date of Discovery: 1878
Discoverer: J.L. Soret
Name Origin: Form the Latin word Holmia (Stockholm)
Uses: nuclear reactors
Obtained From: gadolinite

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Name: Erbium
Symbol: Er
Atomic Number: 68
Atomic Mass: 167.26 amu
Melting Point: 1522.0 °C (1795.15 K, 2771.6 °F)
Boiling Point: 2510.0 °C (2783.15 K, 4550.0 °F)
Number of Protons/Electrons: 68
Number of Neutrons: 99
Classification: Rare Earth
Crystal Structure: Hexagonal
Density @ 293 K: 8.795 g/cm³
Color: grayish

 

 

Atomic Structure

Number of Energy Levels: 6   First Energy Level: 2 Second Energy Level: 8 Third Energy Level: 18 Fourth Energy Level: 30 Fifth Energy Level: 8 Sixth Energy Level: 2

 

Isotopes

Isotope	Half Life
Er-162	Stable
Er-164	Stable
Er-166	Stable
Er-167	Stable
Er-168	Stable
Er-169	9.4 days
Er-170	Stable
Er-171	7.5 hours
Er-172	2.1 days

 

Facts

Date of Discovery: 1843
Discoverer: Carl Mosander
Name Origin: Ytterby (a town in Sweden)
Uses: ceramics
Obtained From: heavier rare earth minerals

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Name: Thulium
Symbol: Tm
Atomic Number: 69
Atomic Mass: 168.9342 amu
Melting Point: 1545.0 °C (1818.15 K, 2813.0 °F)
Boiling Point: 1727.0 °C (2000.15 K, 3140.6 °F)
Number of Protons/Electrons: 69
Number of Neutrons: 100
Classification: Rare Earth
Crystal Structure: Hexagonal
Density @ 293 K: 9.321 g/cm³
Color: silverish

 

 

Atomic Structure

Number of Energy Levels: 6   First Energy Level: 2 Second Energy Level: 8 Third Energy Level: 18 Fourth Energy Level: 31 Fifth Energy Level: 8 Sixth Energy Level: 2

 

Isotopes

Isotope	Half Life
Tm-168	93.1 days
Tm-169	Stable
Tm-170	128.6 days
Tm-171	1.92 years
Tm-172	2.65 days

 

Facts

Date of Discovery: 1879
Discoverer: Per Theodor Cleve
Name Origin: From Thule (ancient name of Scandinavia)
Uses: power for portable x-ray machines
Obtained From: gadolinite, euxenite, xenotime

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Name: Ytterbium
Symbol: Yb
Atomic Number: 70
Atomic Mass: 173.04 amu
Melting Point: 824.0 °C (1097.15 K, 1515.2 °F)
Boiling Point: 1466.0 °C (1739.15 K, 2670.8 °F)
Number of Protons/Electrons: 70
Number of Neutrons: 103
Classification: Rare Earth
Crystal Structure: Cubic
Density @ 293 K: 6.98 g/cm³
Color: Silvery

 

 

Atomic Structure

Number of Energy Levels: 6   First Energy Level: 2 Second Energy Level: 8 Third Energy Level: 18 Fourth Energy Level: 32 Fifth Energy Level: 8 Sixth Energy Level: 2

 

Isotopes

Isotope	Half Life
Yb-168	Stable
Yb-169	32.03 days
Yb-170	Stable
Yb-171	Stable
Yb-172	Stable
Yb-173	Stable
Yb-174	Stable
Yb-175	4.19 days
Yb-176	Stable

 

Facts

Date of Discovery: 1878
Discoverer: Jean de Marignac
Name Origin: Ytterby (a town in Sweden)
Uses: metallurgical and chemical experiments
Obtained From: yttria, monazite, gadolinite, xenotime

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Name: Lutetium
Symbol: Lu
Atomic Number: 71
Atomic Mass: 174.967 amu
Melting Point: 1656.0 °C (1929.15 K, 3012.8 °F)
Boiling Point: 3315.0 °C (3588.15 K, 5999.0 °F)
Number of Protons/Electrons: 71
Number of Neutrons: 104
Classification: Rare Earth
Crystal Structure: Hexagonal
Density @ 293 K: 9.85 g/cm³
Color: silvery

 

 

Atomic Structure

Number of Energy Levels: 6   First Energy Level: 2 Second Energy Level: 8 Third Energy Level: 18 Fourth Energy Level: 32 Fifth Energy Level: 9 Sixth Energy Level: 2

 

Isotopes

Isotope	Half Life
Lu-172	6.7 days
Lu-172m	3.7 minutes
Lu-173	1.37 years
Lu-174	3.3 years
Lu-174m	142.0 days
Lu-175	Stable
Lu-176	3.6E10 years
Lu-177	6.68 days
Lu-177m	160.7 days

 

Facts

Date of Discovery: 1907
Discoverer: Georges Urbain
Name Origin: From Lutetia (ancient name of Paris)
Uses: No uses known
Obtained From: gadolinite, xenotime