American Heritage® Dictionary of the English Language, Fourth Edition
- n. A colorless, radioactive, inert gaseous element formed by the radioactive decay of radium. It is used as a radiation source in radiotherapy and to produce neutrons for research. Its most stable isotope is Rn 222 with a half-life of 3.82 days. Atomic number 86; melting point -71°C; boiling point -61.8°C; specific gravity (solid) 4. See Table at element.
- n. A radioactive chemical element (symbol Rn, formerly Ro) with atomic number 86, one of the noble gases.
GNU Webster's 1913
- n. (Chem.) An intensely radioactive gaseous element produced by the radioactive decay of radium-226, which is the main isotope of radium found in pitchblende. Chemically it is an inert noble gas. Its atomic symbol is Rn. It has an atomic number of 86. The radon isotope produced by decay of radium has an atomic weight of 222.017, and this isotope decays by alpha emission with a half-life of 3.82 days. Numerous other isotopes have been observed, all radioactive and all having half-lives shorter than that of radon-222. Radon was discovered by M. and Mme. Curie, of Paris, in their studies of the radioactive substances in pitchblende. Radon was originally called
radium emanationor exradio.
- n. a radioactive gaseous element formed by the disintegration of radium; the heaviest of the inert gasses; occurs naturally (especially in areas over granite) and is considered a hazard to health
- Contraction of radium emanation, since the element appears in the radioactive decay of radium. (Wiktionary)
- rad(ium) + -on2. (American Heritage® Dictionary of the English Language, Fourth Edition)
“Checking for radon is an inexpensive task using one of the short - or long-term radon test kits we reviewed.”
“The resulting microscopic particles were known as radon “daughters,” and the daughters were all radioactive, too.”
“Usually, radon is found in your basement (underground deposits of uranium decay and produce the gas) -- but when the radon specialist inspected Dr. Sugarman's house -- he found radon in her kitchen.”
“Checking for radon is an inexpensive task using one of the short- or long-term radon test kits we reviewed.”
“TO find a certified technician to determine whether radiation or radon is emanating from a granite countertop, homeowners can contact the American Association of Radon Scientists and Technologists (aarst. org).”
“The word radon will not appear in the Lung Cancer Mortality Reduction Act.”
“Long-term radon testing revealed that the radon level near our countertops is very low but the level in the basement is 3.6 picocuries per liter.”
“Consumer Reports is preparing a report on short-term radon tests kits for the September 2008 issue of Consumer Reports, on sale and online this August.”
“(Look for our report on short-term radon tests kits in the September 2008 issue of Consumer Reports, on sale and online this August.)”
“Look for our report on short-term radon tests kits in the September 2008 issue of Consumer Reports, on sale and online this August.”
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It's a hazardous world out there...poison all around. I've tried not to include too many drugs (including medicines) and have ignored the fact that too much of anything can poison you. We're going ...
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