Its appearance is not known
but i think it may be a colour like grey-green
Cesium Nitride
Cs3N
Formula = Cs3N
Cs3N is cesium nitride.
The name phosphite is according to IUPAC reserved for PO33- ion, so Cesium phosphite would be Cs3PO3 However no compounds containing PO33- are known to exist. Hypothetical compounds containing it are often used in naming exercises by teachers/colleges/web sites. Phosphite in common use refers to HPO32- ion (IUPAC name phosphonate) and this is the formula taught in some parts of the world, cesium phosphite would therefore be Cs2HPO3
This is the chemical formula of calcium nitride.
K3N is not an element. It is a compound known as potassium nitride.
Cesium Sulfide
The formula for copper(I) nitride is Cu3N. Nitride has a valency of -3
Cesium bromide. In a binary compound (2 constituent elements,) the non-metal becomes an "-ide" regardless of its normal name. So, oxygen becomes oxide, chlorine becomes chloride, nitrogen becomes nitride, etc...
Magnesium(I) Nitride is the name of Mg3N.
126 protons are in nitride.