Solid potassium superoxide同potassium oxide的顔色分別係？

Potassium superoxide (KO2) is described as being somewhere between yellow and orange depending on what source you look at. In my experiment, potassium superoxide is rather yellow than orange.

Below is a diagram showing some potassium superxode powder on a piece of watch glass.

http://mattson.creighton.edu/KO2/Dish_KO2.JPG

圖片參考：http://mattson.creighton.edu/KO2/Dish_KO2.JPG


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Potassium burns in air with a lilac flame to give a mixture of potassium peroxide (K2O2) and potassium superoxide (KO2).
2K(s) + O2(g) → K2­O2(s)
K(s) + O2(g) → K­O2(s)

Why the product is peroxide or superoxide but not common oxide?
Potassium is a very reactive metal, while oxygen is a very reactive non-metal. Therefore, the reaction between them is very fast. In such a very fast reaction, O2 molecule prefers to give peroxide ion ([O-O]2-) or superoxide ion ([O-O]-), because such conversion does not involve the complete breaking of the O=O bond. This is known as “kinetic control”.
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Solid(powdered form) 既 potassium superoxide 通常會描述為黃色 (化學式為 KO2), 而 solid(powdered form) 既 potassium oxide 係白色(化學式為 K2O).
當 potassium oxygen(burn in air), potassium oxide 是主要生成物,
只有少量 potassium superoxide 會生成 (少於1%).

Solid(powdered form)既potassium superoxide好似係橙色，係唔係.我真是5知
solid(powdered form)既potassium oxide係白色..

potassium+oxygen(burn in air)會出左white powder + purple的flame
burn之後的white powder是potassium oxide



5知岩5岩..^^