The taste of salts

But lead acetate does not taste sour, while Pb(II) is an acidic cation! It tasts very sweet just like sugar!

And copper sulfate tastes very bitter.

I wonder how Hg(CN)2 tastes like

Quote: Originally posted by hissingnoise

NH4NO3 is very unpleasantly salty, though what I tasted was very impure.

Some salts are not worth tasting because of their toxicity. Salts of Lead, barium, cadmium, nickel or hexavalent chromium compounds. IIRC barium chloride can be lethal at 0.8 grams! One small crystal might be enough for diarhea and heart spasms. Lead has the capability to find phosphate in the body and deposit in your bones accumulating! I don't even want to guess what cadmium does.

The book Die organischen Geschmacksstoffe by Georg Cohn has about two pages mentioning inorganic compounds and salts, some examples are HMnO4, KMnO4 which taste sweetly bitter and astringent.

Sweetly (cooling) and alkaline is borax. Sweet to sweetly: sodium hexametaphosphate, zinc bromide, etc.

Sweetly tart (astringent): nickel salts, beryllium salts, samarium salts, potassium osmate, aluminium sulfate, alum, didymium sulfate.

Salty: LiF, NaF, NH4F (pungent), KBr (pungent), KI (spicy), disodium orthophosphate, ammonium bicarbonate, rubidium sulfate and perchlorate, etc. Salty and astringent: zinc chloride.

Bitter: phosphine, BaCl2, SrCl2, potassium sulfite, calcium nitrate (cooling), ammonium sulfate (spicy), potassium bromate, soluble magnesium salts, sodium tungstate, sodium vanadate, etc.

Don't particularily recommend munching on any of those, especially the heavy metal compounds.

I tried ammonium sulfate and didn't notice the bitterness much, all I can say is "it tastes like burning".

Reminds of the time I tasted vanillin only to find out that burns the tongue too.

[Edited on 16-8-2009 by Formatik]

We have a number of very good chemists here!

Quote: Originally posted by chloric1

...I don't even want to guess what cadmium does.

The 'saltiness' of an ion seems to be related to it's ionic radius and hydration sphere. Most metal salts can invoke sweetness, saltiness, bitterness, and sourness, depending on their concentration. Sodium only presents sweetness and saltiness, lithium adds sourness that sometimes is confused with bitterness. Some can also cause a metallic taste, alkaline salts seem to do this more.

As the ionic radius moves away from that of sodium, the perceived bitterness generally increases. In the alkali metals the series goes Li>Na>K>Rb>Cs. Ammonium is an exception, it is saltier than sodium even though its radius is close to Rb; ammonium's taste is complicated by the acidic nature of its salts, which adds a sour or sharp element to the taste. Lithium salts tend to be slightly alkaline and often have a sour overtone as the concentration increases.

Ca(2+) is saltier than Na(1+), having nearly the same ionic radius 0.99 vs 1.02 Å, but becomes bitter as the concentration increases. The alkaline earth series is Mg < Ca &gt; Sr &gt; Ba with the ends of the series being bitter over salty.

The halides become less salty and more bitter as the ionic radius increases. This is less pronounced than with the cations, KI is distinctly bitter while NaI is less so, NaBr is mostly salty while KBr is mixed salty-bitter.

Oxi anions seem give a cooling sensation to a greater or lesser degree, NO3&gt;ClO3&gt;ClO4&gt;SO4. Weaker acids, CO3(2-) and SO3(2-), can give sour or bitter sensations as well, likely as their solutions are generally slightly alkaline.

A small amount of acidic nature is perceived more as 'sharpness' rather than 'sour'. Sharp or slightly bitter tastes combined with distinct saltiness are often described as 'spicy'.

Be does taste very sweet in low concentrations, apparently it is sweeter than sucrose, going bitter as the concentration increases. Lead compounds taste sweet as well, in both cases this is attributed to the size of the ion and hydration sphere. Some of the other metals' salts taste sweet at low concentrations but rapidly turn bitter as the concentration is increased.

Not even sure if sulfates or sulfuric has any role in body chemistry of humans but AFAIK the sulfate ion itself is not appreciably toxic. Although sulfuric acid mists are stated to be carcingenic on prolonged exposure. But in my opion, the pulmonary problems and possible COPD would be more worrisom for me than some vague cancer possibility. The only sulfates that in my opinion are worth tasting are sodium sulfate and ammonium sulfate. Sodium sulfate is so cooling and mild while ammonium sulfate is very salty without making you cringe. I might try lithium sulfate but it might taste like magnesium sulfate(YUK!).

Perhaps he is the one who also define the taste of the nitrite salts

I'd think one could get a small enough amount to be safe, especially if they had the antidote right next to them - though probably back then... They probably didn't have the antidote.

I actually tasted sodium nitrite but without putting it in my mouth!

When I had that H2S exposure accident, I injected a fair amount of NaNO2, and after the initial burn in the arm, had a salty/bitter taste in the mouth.. This happens quite often during IV injections of products, I have been told this happens with good quality meth: you get the slight taste after an IV..

I suppose it depends on the individual too......not getting too metaphysical about it all

Quote: Originally posted by sparkgap

"Potassium Chloride tastes pretty much like Sodium Chloride." You think? I can differentiate KCl and NaCl blindfolded. KCl has a bitter aftertaste that lingers for me... blech.

Nobody mentioned alkaline substances. So I will.

Ammonium hydroxide in less than 5% taste much like baking soda.

Sodium Carbonates starts off like the bicarbonate but ends with a shocking strong bite. I think this is the threshold of alkalinaty tasting as everything more basic is just going to taste outright caustic ie sodium metasilicate, trisodium phosphate etc etc. Incidently, I use TSP to soften cooked and baked on food residues on my frying pans.