And that is
the most common ELEMENT
The Big Bang Theory Season 7, Episode 3
The ELEMENT was found
because of you,
The Big Bang Theory Season 7, Episode 6
"What is the lightest ELEMENT on Earth
with no stable isotope?"
The Big Bang Theory Season 1, Episode 13
stable super-heavy ELEMENT.
The Big Bang Theory Season 7, Episode 10
is the ELEMENT of surprise.
The Big Bang Theory Season 7, Episode 12