Copernicium (Cn): Bohr Model, Protons, Neutrons & Electrons
Copernicium is element number 112, a superheavy in group 12, period 7. Its atom has 112 protons, 173 neutrons and 112 electrons arranged in 7 shells: 2, 8, 18, 32, 32, 18, 2.
- 112 protons
- 173 neutrons
- 112 electrons
Protons, neutrons and electrons in copernicium
The atomic number of copernicium is 112, so every copernicium atom has 112 protons. A neutral atom has the same number of electrons, 112. The number of neutrons depends on the isotope: neutrons = mass number − atomic number. For copernicium-285, that is 285 − 112 = 173 neutrons. Every isotope of copernicium is radioactive; 285 is the mass number of its most stable one.
How to draw the Bohr model of copernicium
- Draw the nucleus and write 112 p⁺ and 173 n⁰ inside it.
- Draw the first shell and put 2 electrons on it (the first shell holds at most 2).
- Draw the second shell and put 8 electrons on it.
- Draw the third shell and put 18 electrons on it.
- Draw the fourth shell and put 32 electrons on it.
- Draw the fifth shell and put 32 electrons on it.
- Draw the sixth shell and put 18 electrons on it.
- Draw the seventh shell and put 2 electrons on it.
- Check: 2 + 8 + 18 + 32 + 32 + 18 + 2 = 112 electrons, the same as the number of protons.
From potassium onwards the shells don’t simply fill as 2, 8, 8: the fourth shell starts before the third is full, so the real arrangement above (2, 8, 18, 32, 32, 18, 2) is the one to draw.
Electron configuration
The electron configuration of copernicium is [Rn] 7s² 5f¹⁴ 6d¹⁰. As a superheavy it fills an inner d-subshell, and its common ion is variable.
Key facts about copernicium
| Symbol | Cn |
|---|---|
| Atomic number | 112 |
| Relative atomic mass | [285] |
| Group · period · block | group 12 · period 7 · d-block |
| Type | Superheavy |
| State at 25 °C | unknown |
| Electron shells | 2, 8, 18, 32, 32, 18, 2 |
| Electron configuration | [Rn] 7s² 5f¹⁴ 6d¹⁰ |
| Valence electrons | varies (outer shell: 2) |
| Common ion | — |
| Electronegativity (Pauling) | — |
| First ionisation energy | — |
| Atomic radius (empirical) | — |
Where copernicium sits on the periodic table
Frequently asked questions
How many protons, neutrons and electrons does copernicium have?
Copernicium has 112 protons and 112 electrons (atomic number 112). Its most common isotope, copernicium-285, has 285 − 112 = 173 neutrons.
What is the electron configuration of copernicium?
[Rn] 7s² 5f¹⁴ 6d¹⁰. In shells that is 2, 8, 18, 32, 32, 18, 2.
How many valence electrons does copernicium have?
Copernicium is a superheavy, so its valence electrons are spread over two shells; its outermost shell holds 2.
Where is copernicium on the periodic table?
In group 12, period 7, in the d-block. It is a superheavy.
