Why did Conany ask people to touch the copper plate to see if there was potassium cyanate in his hand?
That is not a copper metal reaction should be more bright after oxide reaction surface to expose the metal luster off the original so it looks brighter and the touch is not in possession of potassium cyanate in the hat
Because potassium cyanate and copper chemical reaction, there is a phenomenon to detect whether there is potassium cyanate.
