Radium (Ra) VS Radon (Rn)
A definitive side-by-side comparison of two essential element profiles.
VS
Main Differences
Radium (Ra) is an element in the alkaline earth metals category with an atomic number of 88. Radon (Rn) is an element in the noble gases category with an atomic number of 86.
Radon (Rn) is 1.8x denser than Radium (Ra). Furthermore, Radium (Ra) melts at a significantly higher temperature than Radon (Rn) (a difference of 771.0 Kelvin).
Where do the names come from?
Ra Radium (Ra) Naming History
The name Radium is derived from the Latin ''radius'', meaning ray.
Rn Radon (Rn) Naming History
The name Radon is derived from radium, as it was first detected as an emission from radium during radioactive decay.
Related Comparisons
Compare
Radium (Ra)
Radon (Rn)
Category
Alkaline Earth Metals
Noble Gases
Atomic Number
88
86
Symbol
Ra
Rn
Atomic Mass
[226] u
[222] u
Group
2
18
Period
7
6
Block
s-block
p-block
Standard State (at 20°C)
solid
gas
Density
5.5 g/cm³
9.73 g/L g/cm³
Melting Point (°C)
696°C
−71°C
Melting Point (°F)
1285°F
−96°F
Melting Point (K)
973 K
202 K
Boiling Point (°C)
1500°C
−61.7°C
Boiling Point (°F)
2732°F
−79.1°F
Boiling Point (K)
2010 K
211.3 K
Year Discovered:
1898
1900
CAS Number
7440-14-4
10043-92-2
Origin of Name:
The name is derived from the Latin ''radius'', meaning ray.
The name is derived from radium, as it was first detected as an emission from radium during radioactive decay.