Diamond oxidation -- covalent bonds

[PatrickP2]

In order for a diamond to oxidize, do the covalent bonds have to be broken? What would happen if I put the diamond in an oven heated to 150 degrees Celcius? Would the reaction start and after some time the stone would disappear?

 

[Borek]

No idea if 150°C will be enough, but yes, diamond heated in the air oxidizes to CO₂.

 

[PatrickP2]

I did a little research and found a study on the oxidation of diamond. It shows that the activation energy is 220 kJ/mol, while the pre-exponential factor is 4.3×10^11 per second. I used the Arrhenius equation and calculated that at 140 C the reaction would take place after 480 million years. I don't know if my reasoning is right, because I have little to do with chemistry and physics, but it seems that 140 C in the oven is not enough after all. :D

Here's the equation I used:
https://www.wolframalpha.com/input?...iusEquation",+"A1"}+->"4.3×10^11++per+second"

 

[Borek]

the reaction would take place after 480 million years

No idea how they define the characteristic time, typically it would be something like half life, so it is not like "reaction takes place after", more like "after comparable time effects of the reaction are obvious".

it seems that 140 C in the oven is not enough after all. :D

Obviously depends on how long you can wait