Sciencemadness Discussion Board
Not logged in [Login ]
Go To Bottom

Printable Version  
Author: Subject: Why does Radium form a nitride and not oxide?
Hazard to Self

Posts: 53
Registered: 9-7-2020
Member Is Offline

[*] posted on 10-7-2020 at 11:15
Why does Radium form a nitride and not oxide?

Curious behavior. Anyone know any other elements that burn to preferentially form a nitride instead of an oxide?

Why does this happen?


Radium is a chemical element with the symbol Ra and atomic number 88. It is the sixth element in group 2 of the periodic table, also known as the alkaline earth metals. Pure radium is silvery-white, but it readily reacts with nitrogen (rather than oxygen) on exposure to air, forming a black surface layer of radium nitride (Ra3N2).

View user's profile View All Posts By User
National Hazard

Posts: 300
Registered: 24-8-2019
Location: Within EU
Member Is Offline

[*] posted on 11-7-2020 at 07:07

Maybe due to the alpha radiation radium emits.
It would be interesting to know why that happens.
Any nuclear hobbyists here?
View user's profile View All Posts By User
Hazard to Others

Posts: 160
Registered: 16-2-2019
Location: UK (North West)
Member Is Offline

Mood: Variable

[*] posted on 11-7-2020 at 10:22

I don't think it to do with the radioactivity as all the alkaline earth metals from magnesium onwards produce a mixture of oxide and nitride when burnt in air, and I think the propensity to produce nitride increases as you go down the group. As to why, I've still no idea.
View user's profile View All Posts By User
International Hazard

Posts: 1350
Registered: 26-4-2008
Location: Neon Thorium Erbium Lanthanum Neodymium Sulphur
Member Is Offline

Mood: pyrophoric

[*] posted on 11-7-2020 at 14:17

It is discussed on this page.

They attribute it to the high lattice energy of the nitrides, due to the highy charged ions involved (2+ and 3-).

BTW, I suspect aluminium also forms nitrides to a lesser extent upon heating in air, as I've noticed a strong ammonia smell when casting aluminium objects and quenching them in water.

I doubt there is a very significant difference in the rate at which Ba and Ra form nitrides or oxides. If there was, surely it would have been exploited to separate Ra from Ba.

[Edited on 11-7-2020 by phlogiston]

"If a rocket goes up, who cares where it comes down, that's not my concern said Wernher von Braun" - Tom Lehrer
View user's profile View All Posts By User

  Go To Top