Hydrogen

Hydrogen (Hydrogen) is the world's lightest gases. Its density is very small, only air 1 / 14. So filling balloons with hydrogen, we must firmly hold hands. Otherwise, as long as it will wash its hands of one or shining on the sky. Hydrogen filling the ball well, often over night, next day do not fly up. This is because hydrogen can钻过Rubber Master invisible small pore and leave the territory. Not only that, but at high temperature, high pressure, hydrogen can even through very thick steel plate. To be able to balloons flying in the air, then they would have to balloon at the gas density smaller (smaller than air).
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Isotope
Exist in nature isotopes have: protium (hydrogen 1), deuterium (2 hydrogen, heavy hydrogen), tritium (3 H, tritium)
Synthesis of artificial isotopes have: 4 hydrogen, hydrogen 5, 6 hydrogen, hydrogen 7
Heavy hydrogen
1. Alias, its English name
Deuterium; Deuterium, Heavy hydrogen.
2. Use
Nuclear research, particle bombardment accelerator, tracer.
3. System Act
(1) from heavy water electrolysis.
(2) by the liquid hydrogen cryogenic distillation fine.
4. Physical and Chemical Properties
MW: 4.032
Triple Point: -254.4 ℃
Liquid density (balanced status, -252.8 ℃): 169kg/m3
Gas density (101.325kPa, 0 ℃): 0.180kg/m3
Hct (101.325kPa, 21.2 ℃): 5.987m3/kg
Gas-liquid volume ratio (15 ℃, 100kPa): 974L / L
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