If you think to the electron configuration of promethium this begin with [Xe].
The noble gas notation for promethium (Pm), which has an atomic number of 61, is [Xe] 6s² 4f⁵. In this notation, [Xe] represents the electron configuration of xenon, the nearest noble gas preceding promethium, and the additional electrons are represented in the 6s and 4f orbitals.
The noble gas that comes before bromine is argon.
The noble gas that comes before iodine is krypton.
Promithethium is a solid not liquid or gas
nobel gas is a gas that cannot react with another gas
No, he was a nobel gas
The radioactive metal, Promethium, is a solid at room temperature and standard pressure. It becomes a liquid at 1040ºC and a gas or vapor at 3000ºC.
The Nobel gas abbreviation for magnesium is Ne.
Yes it is a noble gas
mixture
No, it is a metal.'
[Ar] 3d10 4s2 4p3