लाञ्थनम
57
La
समूह
लागू नहीं
आवर्त
6
ब्लॉक
f
प्रोटॉन
इलेक्ट्रॉन्स
न्यूट्रॉन
57
57
82
सामान्य गुण
परमाणु संख्या
57
परमाणु भार
138.90547
द्रव्यमान संख्या
139
श्रेणी
लैन्थेनाइड्स
रंग
रजत
रेडियोधर्मी
नहीं
From the Greek word lanthanein, to lie hidden
क्रिस्टल की संरचना
सरल हेक्सागोनल
इतिहास
Lanthanum was discovered in 1839 by Swedish chemist Carl Gustav Mosander.
He partially decomposed a sample of cerium nitrate by heating and treating the resulting salt with dilute nitric acid.
From the resulting solution, he obtained a pale brick colored oxide of the new rare earth.
Lanthanum was isolated in relatively pure form in 1923.
He partially decomposed a sample of cerium nitrate by heating and treating the resulting salt with dilute nitric acid.
From the resulting solution, he obtained a pale brick colored oxide of the new rare earth.
Lanthanum was isolated in relatively pure form in 1923.
इलेक्ट्रॉन प्रति शेल
2, 8, 18, 18, 9, 2
इलेक्ट्रॉन कॉन्फिगरेशन
[Xe] 5d1 6s2
Lanthanum is the most reactive of the rare earth metals
भौतिक गुण
अवस्था
ठोस
घनत्व
6.145 g/cm3
गलनांक
1193.15 K | 920 °C | 1688 °F
क्वथनांक
3737.15 K | 3464 °C | 6267.2 °F
विलय ऊष्मा
6.2 कि.जूल/मोल
वाष्पीकरण ऊष्मा
400 कि.जूल/मोल
विशिष्ट ऊष्मा क्षमता
0.195 जूल/ग्राम•केल्विन
पृथ्वी की पपड़ी में प्रचुरता
0.0034%
ब्रह्मांड में प्रचुरता
2×10-7%
सी ए एस संख्या
7439-91-0
PubChem सी.आई.डी. संख्या
23926
परमाण्विक गुण
परमाणु का त्रिज्या
187 pm
संयोजी त्रिज्या
207 pm
इलेक्ट्रोनेगेटिविटी
1.1 (पाइलिंग पैमाना)
आयनीकरण ऊर्जाएं
5.5769 eV
परमाणु आयतन
22.5 से.मी.३/मोल
तापीय चालकता
0.135 W/cm·K
ऑक्सीकरण स्थितियां
2, 3
उपयोग
Lanthanum is used in large quantities in batteries for hybrid automobiles.
It is also used to make night vision goggles.
Small amounts of lanthanum, as an additive, can be used to produce nodular cast iron.
Lanthanum carbonate is used to reduce blood levels of phosphate in patients with kidney disease.
It is also used to make night vision goggles.
Small amounts of lanthanum, as an additive, can be used to produce nodular cast iron.
Lanthanum carbonate is used to reduce blood levels of phosphate in patients with kidney disease.
Lanthanum and its compounds are considered to be moderately toxic
समस्थानिक
स्थिर आइसोटोप
139Laअस्थिर समस्थानिक
117La, 118La, 119La, 120La, 121La, 122La, 123La, 124La, 125La, 126La, 127La, 128La, 129La, 130La, 131La, 132La, 133La, 134La, 135La, 136La, 137La, 138La, 140La, 141La, 142La, 143La, 144La, 145La, 146La, 147La, 148La, 149La, 150La, 151La, 152La, 153La, 154La, 155La