Reaction of alkaline earth metals with O 2

[anigeo]

reaction of alkaline Earth metals with O₂

i just got in my textbook that Ba,Ca,Sr is kept in paraffin but Mg and Be are not as they form a protective coat of oxide on their surface.i don't get a clue about this .could anyone explain me this?

 

[Borek]

I don't understand what you don't understand - alkaline metals differ, the lower you are in the periodic table, the more reactive they are. Be and Mg are mildly reactive, they can be kept in contact with the air, those below react violently with the air oxygen, so they are kept submerged in an inert liquid.

 

[anigeo]

I don't understand what you don't understand - alkaline metals differ, the lower you are in the periodic table, the more reactive they are. Be and Mg are mildly reactive, they can be kept in contact with the air, those below react violently with the air oxygen, so they are kept submerged in an inert liquid.

what about the coat of oxide on the surface of Mg and Be that prevents them from being attacked by acids.

 

[Borek]

what about the coat of oxide on the surface of Mg and Be that prevents them from being attacked by acids.

Again, I don't understand what you don't understand and I can only repeat, almost word for word, what you wrote. Fresh surface of the Mg and Be reacts quickly with the air oxygen. Produced oxides stick strongly to the surface and are relatively nonreactive, thus they isolate bulk metal below from the further reactions.

 

[LudusRex]

The reaction of alkaline earth metals with oxygen (O2) is a highly exothermic process. When exposed to oxygen, elements such as barium (Ba), calcium (Ca), and strontium (Sr) react vigorously, producing oxides of these metals. However, magnesium (Mg) and beryllium (Be) have a different reaction with oxygen due to their unique properties.

Mg and Be are more reactive compared to Ba, Ca, and Sr. When exposed to oxygen, they form a thin layer of oxide on their surface, which acts as a protective barrier. This layer prevents further reaction with oxygen and protects the underlying metal from corrosion.

On the other hand, Ba, Ca, and Sr are less reactive and have a higher melting point. When exposed to oxygen, they form a thick layer of oxide on their surface, which does not act as a protective barrier. This layer can continue to react with oxygen, leading to the formation of more oxides.

To prevent this continuous reaction, Ba, Ca, and Sr are kept in paraffin, which acts as a protective coating. This allows the metals to be stored and handled safely without reacting with oxygen.

In summary, the reaction of alkaline earth metals with oxygen is influenced by the reactivity and properties of each element. While Mg and Be form a protective layer of oxide, Ba, Ca, and Sr require a protective coating to prevent further reaction with oxygen.