It's lighter than air and is normally found as a molecule, H₂; over a certain activation energy makes a chain reaction with O₂, releasing a lot of heat as a colorless flame; this energy can be harnessed for clean energy production and atomic bombs (cf. Li)

It boils at 4°K and at low temperature behaves like a superfluid, which can be used in MRI technology; it is a byproduct of hydrogen fusion in star cores and it forms as an alpha particle is released in radioactive decay; most naturally occurring helium on our planet comes from this process

Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.

Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.

Due to its ability to do 4 bonds, it forms such a variety of molecules that it stemmed its own branch of chemistry: organic chemistry. Some examples are graphite, graphene, fullerene and diamond. In the past years a plethora of new forms of C was found.
The tetrahedrons of diamond are way more resilient than the irregularly spaced hexagons of graphite. Follows a graph showing the relative conductivity of some carbon compounds.

A very reactive molecule, due to its high electronegativity. Liquid fluorine is light yellow. To work with fluorine, nickel containers are used, because nickel reacts with fluorine to form a protective compound on the surface. With the same principle, fluoride in toothpaste helps the apatite in the teeth form a protective layer from acids.

Emits light when high voltage is applied

Yellow-green gas, heavier then air, reacts with almost all metals, very poisoness due to its reactivity, if in a bond completely inert

Fine as a single atom and due to this it doesn't vibrate (application in studying infrared spectra), colourless gas and liquid, shines blue under high voltage, very unreactive but can make compunds with fluorine