I think I asked this awhile back before this forum was created. I still have trouble understanding how, upon heating (in a presumably normal atmosphere at STP) we have alkaline metal oxides such as K2O 'decompose' upon heating at around 1500 degrees Celsius. My question is : decompose into what? Someone has mentioned that the alkaline metals form hydroxides at those temperatures - but aren't hydroxides dehydrated themselves into regular oxides (as in the case of MgOH into MgO) upon heating?
Wikipedia says that potassium oxide decomposes into potassium peroxide and potassium when headed above 350 degrees Celsius.
Well, i'm not sure, but K20 is not an alkaline, unless you meant KOH. You need an OH group in any base, unless of cause its alkyl, then you have alcohol. My guess is that a perioxide is formed along with the metal. But the general rule is a product of water and metal oxide. NaOH ---> Na2O + H2O
I would assume that you get Potassium Metal and Oxygen for K2O. Now if you mean KOH then I would think you would get Potassium Oxide and water. heat 2K2O >>> 4K+O2 heat 2KOH >>> K2O+H2O