Lithium vs Cobalt
Lithium is a metal (alkali metal); Cobalt is a metal (transition metal).
The differences in plain English
- Both are solids at room temperature.
- Cobalt is denser, about 16.7 times more than Lithium (8.9 against 0.534 g/cm³).
- Cobalt melts at 1495 °C, far above Lithium at 180 °C.
- An atom of Cobalt is about 8.5 times heavier than an atom of Lithium (58.93 u against 6.94 u).
- Cobalt pulls electrons more strongly in a bond (electronegativity 1.88 against 0.98).
Side by side
| Lithium | Cobalt | |
|---|---|---|
| Atomic number | 3 | 27 |
| Symbol | Li | Co |
| Family | Alkali metal | Transition metal |
| Group / period | 1 / 2 | 9 / 4 |
| State at room temperature | Solid | Solid |
| Atomic mass | 6.940 u | 58.933 u |
| Density | 0.534 g/cm³ | 8.9 g/cm³ |
| Melting point | 180 °C | 1495 °C |
| Boiling point | 1330 °C | 2927 °C |
| Electronegativity | 0.98 | 1.88 |
| First ionisation energy | 520.2 kJ/mol | 760.4 kJ/mol |
| Electron configuration | [He] 2s1 | [Ar] 3d7 4s2 |
| Discovered by | Johan August Arfwedson | Georg Brandt |
Lithium
Lithium is a soft, silvery metal and the lightest solid element. A lump of it feels oddly weightless in the hand, with roughly half the density of water. It is the first of the alkali metals, the family that fills the left-hand column of the periodic table and reacts eagerly with water.
- Lithium is the lightest metal and the least dense solid element.
- Lithium was one of only three elements created in significant amounts in the Big Bang.
Cobalt
For most of history cobalt meant one thing: blue. Cobalt compounds gave Egyptian glass, Persian tiles, Chinese porcelain and Dutch Delftware their deep blue colours long before anyone knew the metal existed. Today cobalt has a very different reputation, as the critical metal in rechargeable batteries, jet engines and cancer treatment, and as a metal whose mining raises hard ethical questions.
- Cobalt, isolated in 1735, was the first metal to be discovered since ancient times.
- Vitamin B12 is the only vitamin that contains a metal atom, a single cobalt at its centre.
Colour the bubbles by density or melting point and the difference jumps out.
More comparisons
Data from Periodic-Table-JSON (CC BY-SA); temperatures rounded to the nearest degree. Written by Anthony.