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Radium
উপাদান 88 · 226.02541 u
Radium is a highly radioactive metal once widely used in luminous paint.
Physical Properties
| পদাৰ্থ | 226.02541 u |
| ঘনত্ব | 5.5 g/cm³ |
| Melting Point | 973.0 K |
| উত্তাপৰ বিন্দু | 2010.0 K |
| আকৃতি | Silvery-white metallic |
| State at Room Temp | Solid |
রাসায়নিক বৈশিষ্ট্যসমূহ
| ইলেকট্ৰোনেজেটিভিটি | 0.9 (Pauling) |
| 1- তম আইনাইজেশন শক্তি | 509.3 kJ/mol |
| ইলেকট্ৰন | 9.65 kJ/mol |
| Oxidation States | +2 |
প্ৰমাণপত্ৰৰ বৈশিষ্ট্য
| ইলেকট্ৰন | [Rn] 7s2 |
| পৰমাণু | 221.0 pm |
| কোভালেন্ট বেৰিয়াড | 221.0 pm |
| Van der Waals Radius | 283.0 pm |
ডিস্কভাৰী
| আবিষ্কাৰ কৰা হৈছে | Marie Curie, Pierre Curie |
| আবিষ্কাৰৰ বছৰ | 1898 |
| অৱস্থান | Paris, France |
| Named After | Latin 'radius' meaning ray |
বিষয়ে Radium
Radium is a luminous, silvery-white radioactive metal discovered by the Curies. It glows blue due to intense radioactivity. The 'Radium Girls' who painted watch dials suffered tragic radiation poisoning.
Uses & Applications
Formerly used in luminous paint and quack medicine. Now mostly replaced in radiation therapy.
মজা কথা
The 'Radium Girls' who painted luminous watch dials suffered horrific poisoning, leading to landmark workplace safety laws.
আইসোটোপ
| Mass Number | অভাৱ | হাফ-লাইফ | Stable |
| 223 | - | 11.43 days | No |
| 224 | - | 3.6319 days | No |
| 226 | - | 1600 years | No |
| 228 | - | 5.75 years | No |
ইলেকট্ৰন
[Rn] 7s2