bromine is a famous element that was used as poisonus gas also arsenic was used it is a more famous one that was more commonly used
The element thallium is a poisonous metal that can cause a person's tongue to turn black or discolored when ingested in toxic amounts. Thallium poisoning can lead to serious health effects, including damage to the nervous system and other organs.
your tongue turns black
Black light
One possible poison that can turn your tongue black is bismuth subsalicylate, commonly found in medications like Pepto-Bismol. This discoloration is temporary and considered harmless. If you suspect poisoning or experience any severe symptoms, seek medical help immediately.
These are silver halides as AgCl and AgBr.
Tannin is a natural chemical found in acorns which is poisonous to humans. When you boil acorns in water, the tannins are released and turn the water black. this could possibly turn you tongue black if you drink it.
It means there's no blood transmission to the tongue.
the heating element turns black because it heats up all the water xxxx I think this is likely to be because your water supply is acidic (pH less than 7). This can dissolve the element over time. Probably best to replace the kettle with one with a concealed element.
Chow chows tongues are blue/purple. You should search some pictures of them.
Phosphorus is an element that turns white when exposed to air. When pure, it is a colorless and transparent waxy solid.
Heroin is dark brown-light brown, black tar is powder that turns sticky and tar like when warm. It smells like vinegar and is very bitter to the tongue.
When a cat has difficulty breathing it's tongue turns blue to indicate that it is not getting oxygen to it's system.