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Silver nitrate can burn and causes VERY permanent brown stains on almost everything it touches. Stains won't be evident until exposed to UV light.
Recently for a biology project, we had to investigate a local ecosystem. In this investigation, i had acquired some water from the aquatic environment (pond) which contains various living things. I did a salt test on it, H2O + AgNO3 and at first it became cloudly like it was expected to. However, when i put it in the sun for a few minutes, obvious supply of Energy, it had turned brown. Is that normal?
So you are saying that the colour turning brown was normal then? Because that test was done to find the amount of salt in the solution, by the amount of precipate formed. It was extremely milky, and I assume from the information youve provided me, that the AgCl was the cause of the brown colour?
IF so, then how didnt the control soloution of pure NaCl react and turn brown?
Silver chloride turns dark when exposed to sunlight, generally it goes purplish then grey then black.This same reaction (or one like it) is used as the basis of photography.However most modern photography relies on the light producing a so called latent image then developing this latent image to get a visible one.Lots of different chemicals can be used as developers and I suspect that some of the "general stuff" present in pond water might well have done two things. First it made the photodecomposition of the silver chloride more rapid and second the "general stuff" in the pond water was oxidised to "brown stuff".