1 D Deuterium
Nonmetal, hydrogen isotope, mass: 2.014 u
Click image to magnify. Vial of glowing pure deuterium, D2. Original size in cm: 1 x 5. How to make gases glow.
Deuterium or heavy hydrogen (2H) is one of the two stable isotopes of hydrogen, it contains one proton and one neutron. Compared to the other, protium (only one proton), it is much rarer, twice as heavy and reacts chemically slightly different to this. Also it glows in a different light. With heavy water, D2O, fast neutrons can be slowed down. Deuterium is used in hydrogen bombs, because it is much easier to fusion than ordinary hydrogen. In the future there could be more reasonable use for it in producing energy in fusion reactors.
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