[jfields87]

Hey! My name is Jon. I am a photographer (abstract, fine-art stuff). I have been reading about a type of uranium based photography and I'm curious as to the chemistry behind it. So far as I can tell the reaction occurs between Uranyl Nitrate and Potassium Ferricyanide, during the development process. How would an equation between those compounds balance when they're reacted with one another?

(UO2(NO3)2) + C6N6FeK4 =

***Note I am NOT actually doing anything with Uranyl Nitrate. I am only curious about the chemistry involved.

[jfields87]

This is what I've got. Though I can't figure out how to balance it.

(UO2)(NO3)2 + K4[Fe(CN)6] = K6(UO2)5[Fe(CN)6]4

Perhaps the photosensitivity of UO2(NO3)2 has something to do with why I cant wrap my head around this. Does anyone know where I should begin?

This is a very old (19th century)photo process, but I'm not sure that the chemical constituencies/reactions have ever been quantified with any degree of certainty.

[Borek]

You will need KNO₃ between products to be able to balance the reaction.

Not that I have a slightest idea about the photochemistry involved in the process.

[Arkcon]

Well, silver based photography, whether conventional silver halide based or even going back to the  daguerreotype process, rely on the selective photoreduction of the silver compound to a grain of silver metal.  The underlying concept is silver is just barely noble enough a metal that it can exist as a compound, but light provides just enough energy to begin to reduce it to a free metal, and developing agents can work on the latent image.  So:

AgBr + λ  Ag^*Br

AgBr +Hydroquinone no reaction

Ag^*Br + hydroquinone  Ag₀ + benzoquinone + Br^- You can balance that, the reaction is actually more complicated

If uranium is chemically similar to silver, you're looking at a similar reaction.  I've never thought of uranium as that noble a metal, it readily forms compounds.  But that's the angle you can work with.  I.e.  balance the silver reaction, and apply it to uranium.

And hey, no need to be shy about uranyl salts, they've been used as colorants in ceramics and glasses for centuries.  You're not building a nuke when you make a photographic solution.  If you're into this sort of thing i.e.  you've made so many daguerreotypes that its become boring, by all means go for this process.

I actually still use film in my camera, everyone else I know has gone digital.