I just read an offhand reference that Na alone doesn’t taste like anything, and that it must be NaCl to taste salty. I had thought that taste receptors used Na+ ions to determine the salty taste.
So what would happen if you licked a slab of sodium metal? Would it be salty?
The reason I ask is because I see that some canned food has loads of sodium, yet they don’t taste salty to me. I don’t know why because salt is usually listed in the ingredients.
If you licked a slab of Sodium it would ignite immediately and burn a hole through your tongue.
Can’t help with the actual question though, but you are correct in saying it’s Sodium that sets off one of the taste receptors on your tongue (as does glutamate, hence monosodium glutamate is used to make your want to eat more of stuff).
Elemental sodium is an extremely reactive substance and is not found anywhere in nature. When you combine sodium and water, you get an explosion, so if elemental sodium hit the saliva of your tongue, you’d be feeling big pain!
It also doesn’t last very long in the air, either. Usually you store it under some type of oil.
(Possible urban legend: college kids throw a chunk of elemental sodium into swimming pool and watch the fireworks. My HS chem teacher told us this one.)
Other dopers please confirm: NaCl tastes like salt on the tongue (duh), but other salts like KCl taste basically the same.
It is sodium in the salt form that imparts the salty taste; not the Na itself.
In high school, we played around with throwing chunks of potassium and sodium into water…plus exposing phosphorus to air. Fun stuff. The potassium, despite supposedly being the more reactive of the two, merely sizzled and caused the water to boil. The sodium, however, sizzled, boiled, ignited, then blasted itself into the ceiling.
It didn’t seem to have any problem in air, merely forming a dull layer of sodium oxide on the outside. The phosphorus, however, was a little more exciting…
Not quite the same. KCl and NH[sub]4[/sub]Cl do not taste like NaCl. They all taste salty, but Na[sup]+[/sup] also stimulates the sweet receptors, and that I think is what gives sodium salts their distinctive flavor.
Tangentially related trivia: some of the early nuclear-reactor powered submarines used liquid sodium as the coolant.
Now that’s dicing with death. Let’s go dive hundreds of feet under the ocean’s surface with a big tub of radioactive metal that explodes when it contacts water! Really! It’ll be fun!! And we can juggle hand grenades while we’re down there!
Its not an urban legend. Our chem teacher did that with potassium. She had a large bowl filled with water, droped a chunk of the material in, and covered it. After a few seconds, a loud BANG was heared and the cover flew in the air.
According to her, potassium is highly reactive, and absorbs oxygen from the water at a very fast rate. That reactions releases loads of hydrogen, which is quite explosive.
Eh, not exactly. The reaction is 2K(s) + 2H[sub]2[/sub]O => 2KOH(aq) + H[sub]2/sub. You’re correct about the hydrogen gas. The reaction is highly exothermic, and the released heat is enough to ignite it in the presence of atmospheric O[sub]2[/sub].