Pm
Promethium
উপাদান 61 · 145.0 u
Promethium is the only radioactive lanthanide with no stable isotopes.
Physical Properties
| পদাৰ্থ | 145.0 u |
| ঘনত্ব | 7.26 g/cm³ |
| Melting Point | 1315.0 K |
| উত্তাপৰ বিন্দু | 3273.0 K |
| আকৃতি | Metallic |
| State at Room Temp | Solid |
রাসায়নিক বৈশিষ্ট্যসমূহ
| ইলেকট্ৰোনেজেটিভিটি | 1.13 (Pauling) |
| 1- তম আইনাইজেশন শক্তি | 540.0 kJ/mol |
| ইলেকট্ৰন | 12.45 kJ/mol |
| Oxidation States | +2, +3 |
প্ৰমাণপত্ৰৰ বৈশিষ্ট্য
| ইলেকট্ৰন | [Xe] 4f5 6s2 |
| পৰমাণু | 183.0 pm |
| কোভালেন্ট বেৰিয়াড | 199.0 pm |
| Van der Waals Radius | 236.0 pm |
ডিস্কভাৰী
| আবিষ্কাৰ কৰা হৈছে | Charles D. Coryell, Jacob A. Marinsky, Lawrence E. Glendenin |
| আবিষ্কাৰৰ বছৰ | 1945 |
| অৱস্থান | Oak Ridge, Tennessee, USA |
| Named After | Prometheus, the Titan of Greek mythology |
বিষয়ে Promethium
Promethium is a radioactive rare earth metal first produced from uranium fission products in 1945. Trace amounts exist in nature from uranium decay. Promethium-147 emits beta radiation.
Uses & Applications
Nuclear batteries, luminous paint, thickness gauges, and beta radiation sources.
মজা কথা
Promethium is named after Prometheus, the Titan who stole fire -- fitting for an element discovered in nuclear reactions.
আইসোটোপ
| Mass Number | অভাৱ | হাফ-লাইফ | Stable |
| 145 | - | 17.7 years | No |
| 147 | - | 2.6234 years | No |
ইলেকট্ৰন
[Xe] 4f5 6s2