Radon Meaning

/ˈɹeɪdɒn/
B2

Definition, CEFR level B2, pronunciation, examples, and quiz.

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nounThe chemical element (symbol Rn, formerly Ro) with atomic number 86. It is an odorless, colorless, chemically inert but radioactive noble gas.

nounRadon-222 (22286Rn), the most stable isotope of said element.

Helium, neon, argon, krypton, xenon and radon are noble gases.
Several measurements show high radon levels in this area.
CEFR Practice Quiz
The basement had high levels of ____ gas, which can cause lung cancer.
CEFR Practice Quiz (Alternate)
The homeowner installed a ventilation system to reduce the levels of ____ gas in the basement.

Contraction of radium emanation, since the element appears in the radioactive decay of radium. By surface analysis, radio- + -on (“suffix for noble gases”).

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CEFR Practice Quiz
The basement had high levels of ____ gas, which can cause lung cancer.
CEFR Practice Quiz (Alternate)
The homeowner installed a ventilation system to reduce the levels of ____ gas in the basement.

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