Radon fluoride (RnF) is a compound of radon, an inert or noble gas. Inert gases are chemically unreactive because their outermost electron shells are completely filled with electrons. However, radon reacts readily with fluorine. The forces between radon's outermost electrons and the atomic nucleus are weakened by distance and the interference of other electrons, enough that the energy gained in creating a radon fluoride molecule is greater than the energy required for promotion of the reaction. The compound is chemically stable, although a powerful oxidizing agent. The usefulness of radon compounds is limited because the longest-lived isotope of radon has a half-life of only 3.82 days. General Name, Symbol, Number Radon, Rn, 86 Chemical series Noble gases Group, Period, Block 18 (VIIIA), 6, p Density, Hardness 9. ... General Name, Symbol, Number Fluorine, F, 9 Series Halogens Group, Period, Block 17 (VIIA), 2, p Density, Hardness 1. ... General Name, Symbol, Number Radon, Rn, 86 Chemical series Noble gases Group, Period, Block 18 (VIIIA), 6, p Density, Hardness 9. ... General Name, Symbol, Number Fluorine, F, 9 Series Halogens Group, Period, Block 17 (VIIA), 2, p Density, Hardness 1. ... The noble gases are a chemical series. ... This article is in need of attention. ... An energy level is a quantified stable energy, which a physical system can have; the term is most commonly used in reference to the electron configuration of electrons, in atoms or molecules. ... Properties The electron (sometimes called negatron; commonly represented as e−) is a subatomic particle. ... General Name, Symbol, Number Fluorine, F, 9 Series Halogens Group, Period, Block 17 (VIIA), 2, p Density, Hardness 1. ... The nucleus (atomic nucleus) is the center of an atom. ... Isotopes are atoms of a chemical element whose nuclei have the same atomic number, Z, but different atomic weights, A. The word isotope, meaning at the same place, comes from the fact that isotopes are located at the same place on the periodic table. ... Half-Life For a quantity subject to exponential decay, the half-life is the time required for the quantity to fall to half of its initial value. ...