As you probably have heard, scientists are creating new chemical elements. What I want to know which is the heaviest and/or heaviest.
Ununquadium (114) is the heaviest known element at present (289 amu). Experiments at Berkeley in 1999 claimed to have created 116 and 118, but the results were retracted because they could not be independently confirmed.
I’ve read somewhere that osmium is the densest element, so, say, a cubic foot of it would weigh more than the same volume of lead, gold, etc., if that’s what you’re looking for.
Osmium, with a density of 22.61 g/cm[sup]3[/sup], is indeed the densest element.
There is another sort of periodic table relating not to electrons but to the numbers of protons and neutrons in the nucleus. These numbers are plotted on the X and Y axes. In this you can see islands of stability as you proceed out along a diagonal line - that is, the elongated point cloud is clumpy. Some believe there is an isolated island of stability way out there, and thus there could be stable atoms with much higher mass than we have reached yet. But how to get there?
what ever happened to lead?
Lead is only half as dense as Osmium. Still, if you want a dense element in industrial quantities, lead is often a good choice.
With a density of only 11.34 g/cm[sup]3[/sup], lead isn’t all that dense.
The Periodic Table as shown to high school students is hardly the only configuration out there, there are a number that are organized for around different concepts. Check the Encyclopaedia Britannica for a sampling and go the the web sites they recommend. http://chemlab.pc.maricopa.edu/periodic/periodic.html showing at least six neato variations.
The densest element known to science is Administratium
http://rs2.ch.liv.ac.uk/~dlc/Administratium.html
Okay, now I’m really interested. I’m no physicist, so I’m confused. I thought that larger atoms got progressively more unstable because the mutual repulsion of the charges on the protons began to overcome the nuclear binding force.
I can understand that the trend might be nonlinear with atomic weight, but I can’t understand how a really really super big atom could be stable. What else is going on that I missed?
“But how to get there?” - How about this? We squeeze about 14 plutonium atoms together, and…
Never mind. I admitted that I wasn’t a physicist, right?
Exgineer, generally it’s true that bigger nuclei are harder to hold together. But there are other things going on as well.
For one example, there are plenty of light atoms that fly apart. Remember “carbon dating”? It watches how thoroughly the less stable Carbon atoms have blown themselves up. Meanwhile much larger atoms can last orders of magnitude longer.
For another example, the elements that have odd numbers of protons in their nuclei are more common in the universe than the elements that have even numbers. Remember that elements go trading electrons around frequently - it’s the number of protons that is really characteristic of an element. So there are clearly things other than small size that favor some numbers of protons over other numbers.
Sorry I don’t know much about why these things are. If you are unbearably interested I could probably dig some things up…