What is the heaviest substance known to man kind?
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What element has the highest density?\n\n    Studies show that osmium and iridium share the highest densities. The reason why there are two is because there are slight discrepancies between the different measurement systems. Speaking of densities, a pinhead's volume of a piece of a dwarf star would weight more than the earth.
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No not all substances. Check out the link below for more details.
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The heaviest person in medical history was Jon Brower Minnoch (USA, 1941–83), who had suffered from obesity since childhood. He was 185 cm (6 ft 1 in) tall and weighed 178 kg (28 st) in 1963, 317 kg (50 st) in 1966 and 442 kg (69 st 9 lb) in September 1976.\nIn March 1978, Minnoch was admitted to University Hospital, Seattle, where consultant endocrinologist Dr. Robert Schwartz calculated that Minnoch must have weighed more than 635 kg (100 st), a great deal of which was water accumulation due to his congestive heart failure.
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Anything that has a higher density than water.
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any type of heavy metal.  Like Mercury for example.
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what foregin substance are you talking about first...
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Do you mean heaviest?  Currently, it has to be that new guy....I don't remember his name.....that is bigger than the Giant.
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Xenon is one of the heaviest gases\n\nAlthough xenon is not toxic, its compounds are highly toxic due to their strong oxidizing characteristics\n\nExcited xenon in a vacuum tube glows blue\n\nThe element's name derives from the Greek word xenon, which means 'stranger'
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nitrogen, probably helium and hydrogen too.
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Nicotine, and it is extremely addictive.  It is also one of the strongest insecticides known to man.  It is a POISON.
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Sulfuric Acid- just learned that today... check the link for more info...\nit is a VERY strong acid!
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Zinc is by far the best element. I also like plutonium.  It's just fun to say. "Plutonium."
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The Daily Mail in the UK says:\n\nPolonium 210 is one of the most toxic substances known to man, with a particle the size of a speck of dust enough to cause the sort of slow, agonising death suffered by Alexander Litvinenko. \n\nWeight for weight, the rare radioactive isotope is 250billion times more toxic than cyanide, and more than a billion times more radioactive than uranium
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Date: Mon Nov 15 22:43:44 1999\nPosted By: Tye Morancy, MadSci Admin\nArea of science: Chemistry\nID: 942629613.Ch Message:\n\n\nHi Nathan,\n\n   That's a cool question to ask...\n\n   The strongest acid on earth is a 80% solution of Antimony Pentaflouride in \nHyrdoflouric Acid.  This acid solution is so strong that they could only \nmeasure a 50% solution.  Just to give you an idea of how strong a 50% solution \nis, it would be equivalent to an acid 1018 times stronger than concentrated \nsulfuric acid!!  Pretty strong huh?\n\n   By the way, this acid is listed in the Guiness Book of World Records as the \nstrongest acid known.\n\n   Thanks for the question Nathan...\n\nTye
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The Most expensive precious metal that can be found naturally is carbon not plutonium because plutonium is man made element and can not be found naturally, the carbon most expensive precious metal ever because diamond made from that metal created by tremindous pressure,heat,and time  below the crust of the earth.
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very strong.\nteeth can break through bone. it is the hardest substance in our body.
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Well, if you found a way to ingest it without it coming contact with oxygen, you would die due to explosions. Mercury is definitely a good candidate for toxicity. Remember the Mad Hatter? Hatters went mad from the mercury that they used to cure the felt used to make hats! \n\nMercury is a metalloid that is liquid at room temperature (the only other liquid metal at room temperature is bromine). \n\nMercury: symbol Hg; atomic # 80; atomic mass 200.59; \n\nMercury is extremely rare naturally and is usually obtained by doing something to cinnabar. \n\nAnything else? I don't know, but I'm sure wikipedia has a lot of info on mercury.