3

Is there any way to dissolve about 10 kg of bronze at room temperature?

If yes, which substance would be the best to use and how would the reaction look like?

Matěj Kripner
  • 33
  • 1
  • 4
  • 2
    Any hints at what exactly you'd consider simple, and also how much bronze you need to dissolve, might be of great help to us. Nitric acid, for example, would certainly do the job; it would also poison you if treated without due respect. With that in mind, welcome to Chem.SE. – Ivan Neretin Jul 26 '16 at 15:11
  • @IvanNeretin Thanks for remarks! I've edited the question. – Matěj Kripner Jul 26 '16 at 15:18
  • 3
    Good grief! Why do you want to do that? – Jon Custer Jul 26 '16 at 15:25
  • 1
    Wow. 10 kg is quite a lot. Still, nitric acid would do the job, but you'll need a lot of it, and you'll get a great deal of toxic fumes, too. I'd definitely not try it at home. I'd probably not try it at the lab either, because why would I, really? – Ivan Neretin Jul 26 '16 at 15:26
  • @JonCuster Actually, I write a Sherlock Holmes chemical story about disappearance of bronze statues :D There will be great revelation mentioning the process used! – Matěj Kripner Jul 26 '16 at 19:47
  • 4
    Letting a glass dagger vanish in a refractive-index matched fluid seems far more impressive to me. – Karl Jul 26 '16 at 23:08

1 Answers1

1

Supposing that the bronze is only 78% copper and 12% tin (and there are no other metals). Nitric acid will dissolve the copper... but this reaction is exothermic, which means it will heat up.

At boiling temperature. Nitric acid will also react with tin to make tin oxide which is soluble. However, if you kept it cool/room temperature with an ice bath, then you would have leftover tin which did not react.

Tin will react with aqua regia to form tin (IV) chloride, but copper is slower to react with aqua regia... so it would be better to use nitric acid first (to dissolve the copper) and then add hydrochloric acid to react with and dissolve the tin. Once again, the reaction between tin and hydrochloric acid (or aqua regia) will proceed much faster with heat, but it will happen at room temperature.

Aqua regia = 1 mole of Nitric acid and 3 moles of hydrochloric acid).

Ben Welborn
  • 1,556
  • 10
  • 12
  • Any guess on just now much nitric and aqua regia that will take? Disposal will be a problem to consider before starting, since it will be hazardous waste. – Jon Custer Jul 26 '16 at 18:38
  • @JonCuster Since its 10kg of bronze... sure; 7.8 kg / the molar weight of copper = recycle the nitrate. Here's a youtube video about making nitric acid. – Ben Welborn Jul 26 '16 at 18:57
  • Thanks for an excellent answer! Could you make an estimate about how long would it take? (considering 10 kg of bronze) – Matěj Kripner Jul 26 '16 at 19:54
  • @MatějKripner It depends on factors like temperature and surface area (powdered bronze might go boom). This is kind of a dangerous reaction, so I would recommend going slowly with lots of ventillation (like outside with fans), and fire extinguishers and perhaps the fire deparment (this could be of some educational importance to them too). Don't breathe any red gas. If possible, start small (grams) and work your way up (to ounces). I could see this reaction taking any where from 1-6 hours to complete (depending on how quickly you feed it and the temperature and thickness/shape of the bronze). – Ben Welborn Jul 26 '16 at 20:54
  • 2
    @MatějKripner I just saw that you are a novelist... with practice and good equipment, I suppose you could dissolve a statue pretty quickly, but if you are considering something like spraying a bronze statue, it's not going to work in a practical way. You would need to soak the statue in a vat of nitric acid. – Ben Welborn Jul 26 '16 at 21:14