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Lanthanum is the namesake of the lanthanide series, used in camera lenses and catalysts.
Physical Properties
| পদাৰ্থ | 138.91 u |
| ঘনত্ব | 6.145 g/cm³ |
| Melting Point | 1193.0 K |
| উত্তাপৰ বিন্দু | 3737.0 K |
| আকৃতি | Silvery-white metallic |
| State at Room Temp | Solid |
রাসায়নিক বৈশিষ্ট্যসমূহ
| ইলেকট্ৰোনেজেটিভিটি | 1.1 (Pauling) |
| 1- তম আইনাইজেশন শক্তি | 538.1 kJ/mol |
| ইলেকট্ৰন | 53.0 kJ/mol |
| Oxidation States | +2, +3 |
প্ৰমাণপত্ৰৰ বৈশিষ্ট্য
| ইলেকট্ৰন | [Xe] 5d1 6s2 |
| পৰমাণু | 187.0 pm |
| কোভালেন্ট বেৰিয়াড | 207.0 pm |
| Van der Waals Radius | 240.0 pm |
ডিস্কভাৰী
| আবিষ্কাৰ কৰা হৈছে | Carl Gustaf Mosander |
| আবিষ্কাৰৰ বছৰ | 1839 |
| অৱস্থান | Stockholm, Sweden |
| Named After | Greek 'lanthanein' meaning to lie hidden |
বিষয়ে Lanthanum
Lanthanum is a soft, ductile, silvery-white metal that tarnishes rapidly. It is found in rare earth minerals like monazite and bastnaesite. It has no biological role.
Uses & Applications
Camera and telescope lenses, catalytic cracking in petroleum, battery electrodes, and lighter flints.
মজা কথা
Lanthanum was 'hidden' inside cerium oxide for 36 years before separation -- fitting since its name means 'to lie hidden'.
আইসোটোপ
| Mass Number | অভাৱ | হাফ-লাইফ | Stable |
| 138 | 0.0009% | - | Yes |
| 139 | 0.9991% | - | Yes |
ইলেকট্ৰন
[Xe] 5d1 6s2