Rb
Rubidium is a highly reactive alkali metal that ignites spontaneously in air.
Physical Properties
| الكتلة الذرية | 85.468 u |
| الكثافة | 1.532 g/cm³ |
| Melting Point | 312.46 K |
| نقطة الغليان | 961.0 K |
| المظهر | Silvery-white metallic |
| State at Room Temp | Solid |
الخواص الكيميائية
| السالبية الكهربائية | 0.82 (Pauling) |
| طاقة التأين الأولى | 403.0 kJ/mol |
| القرب الإلكتروني | 46.9 kJ/mol |
| Oxidation States | +1 |
الخصائص الذرية
| تشكيل الإلكترون | [Kr] 5s1 |
| نصف قطر الذرة | 248.0 pm |
| نصف قطر التكافؤ | 220.0 pm |
| Van der Waals Radius | 303.0 pm |
اكتشاف
| اكتشفها | Robert Bunsen, Gustav Kirchhoff |
| سنة الاكتشاف | 1861 |
| الموقع | Heidelberg, Germany |
| Named After | Latin 'rubidus' meaning deep red, from its bright red spectral lines |
عن Rubidium
Rubidium is a soft, silvery-white metallic element that is the second most electropositive element. It ignites in air and reacts violently with water. It is used in atomic clocks due to its precise spectral lines.
Uses & Applications
Atomic clocks, specialty glass, fireworks (purple color), photocells, and medical imaging.
حقيقة مضحكة
Rubidium atomic clocks are so precise they would not lose a second in several hundred million years.
النظائر
| Mass Number | الوفرة | نصف العمر | Stable |
| 85 | 0.7217% | - | Yes |
| 87 | 0.2783% | 49.23 billion years | No |
تشكيل الإلكترون
[Kr] 5s1