Hydrogen (H)
1s¹. 1 unpaired electron, period 1, group 1, s block.
Element or ion
Type a symbol, a name or an atomic number, add a charge such as Fe3+ or Cl-, or tap an element in the table. Orbitals fill from m = −l up, spin +½ first.
HHydrogen, Z = 1, 1.008 u
1s1
In full: 1s¹
- Blocks block
- Period1
- Group1
- Valence1
- Unpaired1
- MagneticPara
Last electron 1s
- n1shell
- l0s subshell
- m0orbital
- s+½spin up
Bohr orbits of H
En = −13.6 Z²/n² eV, rn = 52.9 n²/Z pm, with Z = 1
- n = 1−13.6 eV52.9 pm
- n = 2−3.4 eV212 pm
- n = 3−1.51 eV476 pm
- n = 4−0.85 eV846 pm
Step by step
- Hydrogen has 1 electrons.
- Fill in (n + l) order: 1s¹.
- Write the subshells in order of n: 1s¹.
- So: 1s¹.
Hydrogen (H): the numbers
| Atomic number | 1 |
|---|---|
| Atomic mass | 1.008 u |
| Period | 1 |
| Group | 1 |
| Block | s block |
| Valence electrons | 1 |
| Unpaired electrons | 1 |
| Magnetic | paramagnetic |
| Last electron | 1s: n = 1, l = 0, m = 0, s = +1/2 |
Hydrogen (H): quick answers
What is the electronic configuration of hydrogen?
Hydrogen has 1 electrons: 1s¹, or 1s¹ in short.
How many unpaired electrons does hydrogen have?
Hydrogen has 1 unpaired electron, so it is paramagnetic. Put one electron in each box of a subshell before pairing (Hund’s rule) to see them.
What are the quantum numbers of the last electron of hydrogen?
The last electron goes into 1s: n = 1, l = 0, m = 0, s = +1/2. Orbitals fill from m = −l up, spin +½ first.