Helium has
an atomic number of two.
The Big Bang Theory Season 7, Episode 3
Not quite accurate.
The Macy's balloons are filled with HELIUM...
The Big Bang Theory Season 4, Episode 24
One time my brothers
made me breathe HELIUM.
The Big Bang Theory Season 12, Episode 6
Forget HELIUM. The real superfluid
is the fruit punch in this mug.
The Big Bang Theory Season 9, Episode 16