Element 1
Hydrogen
Nonmetals
Hydrogen (H) is in the s-block of the periodic table — group 1, period 1.
Hydrogen is a chemical element with chemical symbol H and atomic number 1.
Key data
- Atomic number
- 1
- Atomic mass
- 1.008 u
- Group / Period
- 1 / 1
- Block
- s-block
- Phase at STP
- Gas
- Density
- 0.08988 g/cm³
- Melting point
- -259.2 °C
- Boiling point
- -252.9 °C
- Electron configuration
- 1s1
Periodic table block
Hydrogen is in the s-block (group 1, period 1). Elements land in the s-block when their highest-energy electrons fill an s subshell — this includes hydrogen, helium, and the reactive metals on the far left of the table.
New to this? Periodic table blocks explained: s, p, d, and f
Common uses
- •Rocket fuel
- •Ammonia synthesis
- •Hydrogenation of fats
Discovery
Year: 1766
Discovered by: Henry Cavendish
Named by: Antoine Lavoisier
Frequently asked questions
What is the atomic number of Hydrogen?
Hydrogen has atomic number 1. Its symbol is H and its atomic mass is 1.008 u.
What category of element is Hydrogen?
Hydrogen is classified as nonmetals. It sits in group 1, period 1 of the periodic table.
What block of the periodic table is Hydrogen in?
Hydrogen is in the s-block (group 1, period 1). Its highest-energy electrons occupy the s subshell — you can see this in its electron configuration, 1s1.
What is Hydrogen used for?
Common uses of Hydrogen include: Rocket fuel, Ammonia synthesis, Hydrogenation of fats.
When was Hydrogen discovered?
Hydrogen was discovered in 1766 by Henry Cavendish.
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