[DOC] [TLE] Chemical element - Wikipedia [PAR] A chemical element or element is a species of atoms having the same number of 
protons in ... There are 80 elements that have at least one stable isotope and 38 
that have ... a pure chemical substance consisting of a single element (e.g. 
hydrogen gas). .... Certain elements have no stable isotopes and are composed 
only of... [DOC] [TLE] Abundance of the chemical elements - Wikipedia [PAR] The abundance of a chemical element is a measure of the occurrence of the 
element relative to all other elements in a given environment. Abundance is 
measured in one of three ways: by the mass-fraction (the .... In astronomy, a "
metal" is any element other than hydrogen or helium. This distinction is significant 
because... [DOC] [TLE] Hydrogen, Chemical Element - reaction, water, uses, elements ... [PAR] Its atoms consist (usually) of one proton and one electron. Hydrogen was first ... 
Some experts believe that hydrogen forms more compounds than any other 
element. .... There are only very small traces of tritium in nature. Tritium is a .... 
The Hindenburg disaster ended lighter-than-air air-ship travel for many decades. [DOC] [TLE] Facts About Hydrogen - Live Science [PAR] Jan 23, 2015 ... The most abundant element in the universe, hydrogen is also a promising ... Pure 
hydrogen gas is scarce in Earth's atmosphere and any hydrogen that actually ... 
is just ordinary hydrogen; deuterium, a stable isotope discovered in 1932 ... 14 
times lighter than air, according to "The Principles of Chemistry. [DOC] [TLE] Where Do Chemical Elements Come From? - American Chemical ... [PAR] hydrogen, the simplest chemical element. This hydrogen ... reactions, the nuclei 
of most elements lighter than iron can be formed (fig. 1). Scientists ... form 
elements heavier than iron. up until ... explode. Only in very massive stars (that 
are. [DOC] [TLE] If hydrogen wasn't the lightest element? | The Trek BBS [PAR] Dec 30, 2012 ... One of the things the professor in SMiley said was what if Hydrogen wasn't the 
atomically ... How could there be an element lighter than hydrogen? ... Quark 
matter could exist, but it wouldn't constitute a chemical element. .... It's easy to say 
that 7 minus 12 equals -5, but if there are only 7 flowers in a garden,... [DOC] [TLE] The Origin of The Elements [PAR] Sep 10, 2004 ... The elements that make up our bodies reflect the cosmic ... their parent galaxy
an idea that has developed only within the past fifty ... chemical elements that are 
the raw materials of life were one time part of a stellar life cycle. ... universe where 
the elements heavier than hydrogen and helium are produced. [DOC] [TLE] Chemical Elements - Auburn University [PAR] The periodic table of the elements, which systematizes all known chemical 
elements, ... or periodicity in the known chemical elements, related that 
periodicity to each ... only other lighter-than-air gas is the dangerous, explosive 
element hydrogen. ... One of these spaces corresponds to a situation in which the 
electron spins... [DOC] [TLE] Atoms and Elements | Parts and Properties of an Atom | Compounds ... [PAR] The smallest object you can see under a microscope has more than 10 billion 
atoms . ... For example, water has two atoms of hydrogen and one atom of 
oxygen. ... In most lighter elements the nucleus of each atom has the same 
number of ... Hydrocarbons are compounds that only have hydrogen and carbon 
in them, like... [DOC] [TLE] Hydrogenthe essentials [WebElements Periodic Table] [PAR] Hydrogen gas was used in lighter-than-air balloons for transport but is far too ... 
However it was only much later that it was recognized as an element by ... [See 
History of Chemistry, Sir Edward Thorpe, volume 1, Watts & Co, London, 1914.]. [DOC] [TLE] hydrogen facts, information, pictures | Encyclopedia.com articles ... [PAR] Hydrogen has two stable isotopesforms of the element that differ in mass. ... 
Having just one electron, hydrogen can bond to other atoms in one of

Question: Hydrogen is the only chemical element that's lighter than this one
Answer: helium