Cesium (Cs) — Alkali metal. Atomic number 55.
Soft golden metal
- Atomic number: 55
- Symbol: Cs
- Atomic mass: 132.91 u
- Category: Alkali metal
- State: Solid
- Melting point: 28.45 °C / 301.6 K
- Boiling point: 670.85 °C / 944 K
- Density: 1.93 g/cm³ (20°C)
- Electron configuration: [Xe] 6s1
- Oxidation states: +1
- Electronegativity: 0.79
- Discovered by: Robert Bunsen and Gustav Kirchhoff (1860)
Common uses: Atomic clocks, Photoelectric cells, Drilling fluids
Biological role: No essential biological role.
Frequently Asked Questions about Cesium
What is the atomic number of cesium?
Cesium has an atomic number of 55, meaning each atom contains 55 protons in its nucleus.
What is the atomic mass of cesium?
The standard atomic weight of cesium is 132.91 u (unified atomic mass units).
What category does cesium belong to?
Cesium is classified as a alkali metal.
What is the state of cesium at room temperature?
Cesium is a solid at 20 °C (68 °F).
What is the melting point of cesium?
The melting point of cesium is 28.45 °C / 301.6 K.
What is the boiling point of cesium?
The boiling point of cesium is 670.85 °C / 944 K.
What is the density of cesium?
The density of cesium is 1.93 g/cm³ (20°C).
What is the electronegativity of cesium?
Cesium has a Pauling electronegativity of 0.79.
What is the electron configuration of cesium?
The electron configuration of cesium is [Xe] 6s1.
What are the common oxidation states of cesium?
Cesium commonly exhibits the following oxidation states: +1.
When was cesium discovered?
Cesium was discovered in 1860 by Robert Bunsen and Gustav Kirchhoff.
Is cesium radioactive?
Cesium is a stable element with no naturally occurring radioactive isotopes.
What is the biological role of cesium?
No essential biological role.
What are the common uses of cesium?
Cesium is used for: Atomic clocks; Photoelectric cells; Drilling fluids.
