Hydrogen (H)
Element 1 · reactive nonmetal · group 1, period 1
Hydrogen is element 1, a reactive nonmetal in group 1 and period 1. Its electron configuration is 1s1. That leaves 1 valence electron in the outer shell, with the shells filling 1. Losing its 1 valence electron is the shorter route to a full shell, so it carries a charge of +1, -1.
- 1 protons
- 1 valence e−
- +1, -1
- s-block
Hydrogen Lewis dot structure
Hydrogen has 1 valence electron, so its Lewis symbol carries 1 dot: one single dot.
Draw it in the Lewis structure generator →
Properties
| Atomic number | 1 |
|---|---|
| Symbol | H |
| Standard atomic weight | 1.008 u |
| Group | 1 |
| Period | 1 |
| Block | s-block |
| Category | reactive nonmetal |
| Electron configuration | 1s1 |
| Noble-gas notation | 1s1 |
| Electrons per shell | 1 |
| Valence electrons | 1 |
| Common ionic charge | +1, -1 |
| Electronegativity (Pauling) | 2.2 |
| Protons / electrons | 1 / 1 |
Electron configuration of hydrogen
Orbitals fill from the lowest energy upward. Writing that out for hydrogen gives 1s1, which is 1s1 in plain text.
| Subshell | Electrons | Capacity |
|---|---|---|
| 1s | 1 | 2 |
Hydrogen ion charge
Hydrogen commonly forms ions with a charge of +1, -1.
It has 1 valence electron, so it is 7 short of a full octet and 1 above an empty outer shell. An atom takes whichever route is shorter, which is why the charge comes out as it does.
Common questions
What is the Lewis dot structure of hydrogen?
The symbol H with 1 dot, one for each valence electron: one single dot. Dots go one to a side before any pair up, the same way electrons fill separate orbitals before sharing one.
How many valence electrons does hydrogen have?
Hydrogen has 1 valence electron. For groups 1 and 2 the count is the group number, and hydrogen is in group 1.
What is the electron configuration of hydrogen?
1s1, or 1s1 written from the previous noble gas. Orbitals fill lowest energy first.
What is the charge of hydrogen?
Hydrogen commonly forms ions with a charge of +1, -1. With 1 valence electron it is 7 short of an octet and 1 above an empty shell, so it takes whichever route is shorter.
How many protons, electrons and neutrons does hydrogen have?
A neutral hydrogen atom has 1 proton and 1 electron. Its standard atomic weight is 1.008, so the most common isotope has about 0 neutrons.
Hydrogen in Lewis structures
What the configuration above means in practice. Hydrogen brings 1 valence electron to each of these, and the working on every one of them starts by counting exactly that.
Nearby elements
See the ionic charge of every element →