What is the world's lowest-density solid?How strong is it?
145529
I think it might be Aerogel.\nIt is actually quite strong for its weight, being made up of about 99.8% air\n\nSee this picture of a block of aerogel supporting a bick,\nhttp://www.unitednuclear.com/aerogelc.jpg
601338
Of course.  The diamond is the hardest substance, but definitly not the strongest.  If the diamond were on a suffieciently smooth and hard surface, the diamond would easily succumb to the pressure.\n\nIf diamonds are strong enough to hold up gross weight, how is it that we can cut them with simple hand tools the gem cutters use.  They are not.  Don't confuse hardness with strength.\n\nI think there is a story about a massive diamond found in the US that was smashed on an anvil because it was thought that it would resist the hammer if it were a true diamond.  It ended up being a diamond but was practically worthless compared to the original stone.
477021
Not an element; yes its still the king of hardness\nThere are experiments ongoing with low-speed nuclear bombardment of iridium with smaller nuclei which are producing very thin layers of great density that approaches the hardness of diamond.
683735
The path of least resistance?
470540
http://en.wikipedia.org/wiki/Strength_of_materials
432870
"Scientists using NASA's Rossi X-ray Timing Explorer have estimated the depth of the crust on a neutron star, the densest object known in the universe. The crust, they say, is close to a mile deep and so tightly packed that a teaspoon of this material would weigh about 10 million tons on Earth."\n\nhttp://spaceflightnow.com/news/n0604/24starquake/
318728
we know that mass = volume * density\nin the first case, mass = 278.1g\nvolume of the cube = 3*3*3 = 27 cm^3\ntherefore density = mass/ volume\n density of steel = 278.1/27 = 10.3\nThrefore the mass of 1 cm^3 of steel= volume * density\n                                    = 1 * 10.3\n                                    = 10.3 g\n\nNote: denstiy of any material is always a constant- it is an intrinsic property of the material. It is important to get these concepts right when you study them so that you can have a good foundation for higher studies. Please promise me that once you understand how to do this problem, you will try it on your own. Thanks. goodluck
93653
Depends on temperature. Iridium is most dense at room temperature (22.65 grams per cubic cm) but not at its melting point. See Source
879131
To determine density you also have to know the temperature.  The colder a substance gets, the more dense it becomes (ie. the particles come closer together).  Water is the one odd ball, it becomes most dense at 4 degree C instead of below freezing like most substances.
286779
you mean sphere? because it has the smallest surface area in terms of volume.
546089
This must be when the particles are allowed to come into closest contact so give it its highest  density
965654
I would have said Diamonds but I just found this from physicsweb.org:\n\n    Diamonds are not forever\n\n    Physicists in Germany have created a material that is harder than diamond. Natalia Dubrovinskaia and colleagues at the University of Bayreuth made the new material by subjecting carbon-60 molecules to immense pressures. The new form of carbon, which is known as aggregated diamond nanorods, is expected to have many industrial applications (App. Phys. Lett. 87 083106).\n\n    The hardness of a material is measured by its isothermal bulk modulus. Aggregated diamond nanorods have a modulus of 491 gigapascals (GPa), compared with 442 GPa for conventional diamond. Dubrovinskaia and two of her co-workers - Leonid Dubrovinky and Falko Langenhorst - have patented the process used to make the new material.\n\n    Diamond derives its hardness from the fact that each carbon atom is connected to four other atoms by strong covalent bonds. The new material is different in that it is made of tiny interlocking diamond rods. Each rod is a crystal that has a diameter of between 5 and 20 nanometres and a length of about 1 micron.
385679
Osmium is the densest matter here on planet earth if I recall correctly from chemistry.  Black holes, white dwarves, neutron stars, the big bang singularity... Are all working theories at this point.  Since we can't simulate them in a lab and can't travel to them to sample them, we are stuck with mathematical testing.  So if you want something that you could pick up (you might need a protective suit), then it is osmium.  Otherwise the highest density occurred about 15 billion years ago at the start of the big bang.
1002111
More or less, but be careful about what you're calling a solid. The lower parts of the lithosphere at sufficient temperature and pressure to deforem ductiley, making thema  fluid on a geological timescale
541190
Osmium is the densest element. 22.6 g/ml\nhttp://www.science.uwaterloo.ca/~cchieh/cact/c120/qzelemnt.html
818381
Lower cost and Less weight.\n\nA properly designed Hollow Core Slab will have the same  or greater strength in load bearing characteristics as a Solid core Slab. The Hollow Core can be re-in forced by the Manufacturer\n\nsee the following URL for additional details:\n\nhttp://www.hollowcore.com.au/products/hcore/\n\nHope this assists you.
936613
Of course, aluminum wins as it has the lowest density.  The passivating oxide film makes aluminum non-corrosive, which is a great comfort to the metallurists and structural engineers responsible for keeping these birds in flight, rather than cracked up over an ocean.