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symbol for the element radonradon
, gaseous radioactive chemical element; symbol Rn; at. no. 86; mass no. of most stable isotope 222; m.p. about −71°C;; b.p. −61.8°C;; density 9.73 grams per liter at STP; valence usually 0. Radon is colorless and the most dense gas known.
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(ReadNews) A newsreader for Usenet newsgroups. An enhanced version of rn that includes threads is trn. See Usenet.
References in periodicals archive ?
Following this experience, the Nurse Extern is assigned to an R.
Care is always taken to assure that Nurse Externs DO NOT perform any procedures or activities that are not included in the Program Guidelines, and that Nurse Externs always work under the supervision of an R.
Input for their performance evaluation is obtained from the R.