Fluorine Atomic Number

  1. Fluorine Number Of Protons
  2. Fluorine Atomic Number 9 Meaning
  3. Fluorine Atomic Number 17
  4. Fluorine Group
  5. Fluorine Atomic Number And Symbol
  6. Fluorine Atomic Number 9

Fluorine (F) Atomic Data for Fluorine (F) Atomic Number = 9 Atomic Weight = Reference E95: Isotope: Mass: Abundance: Spin: Mag Moment: 19 F. Fluorine is an element with atomic number 9 and symbol F. Know the Uses of Fluorine, Chemical Properties of Fluorine, Atomic Mass of Fluorine & more at BYJU'S. Answers for Atomic number of fluorine crossword clue. Search for crossword clues found in the Daily Celebrity, NY Times, Daily Mirror, Telegraph and major publications. Find clues for Atomic number of fluorine or most any crossword answer or clues for crossword answers. Fluorine was discovered by Henri Moissan (FR) in 1886. The origin of the name comes from the Latin word fluere meaning to flow. It is a pale yellow to greenish gas, with an irritating pungent odour. Fluorine is a extremely reactive, flammable gas. It reacts violently with many materials. It is toxic by inhalation or ingestion.

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Fluorine Atomic Number

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Fluorine Number Of Protons

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Stefan SchneiderSee All ContributorsAtomic
Senior Research Scientist, Air Force Research Laboratory, Edwards Air Force Base, Calif.
Alternative Title: F

Fluorine (F), most reactive chemical element and the lightest member of the halogen elements, or Group 17 (Group VIIa) of the periodic table. Its chemical activity can be attributed to its extreme ability to attract electrons (it is the most electronegative element) and to the small size of its atoms.

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Element Properties
atomic number9
atomic weight18.998403163
melting point−219.62 °C (−363.32 °F)
boiling point−188 °C (−306 °F)
density (1 atm, 0 °C or 32 °F)1.696 g/litre (0.226 ounce/gallon)
oxidation states−1
electron config.1s22s22p5


The fluorine-containing mineral fluorspar (or fluorite) was described in 1529 by the German physician and mineralogist Georgius Agricola. It appears likely that crude hydrofluoric acid was first prepared by an unknown English glassworker in 1720. In 1771 the Swedish chemist Carl Wilhelm Scheele obtained hydrofluoric acid in an impure state by heating fluorspar with concentrated sulfuric acid in a glass retort, which was greatly corroded by the product; as a result, vessels made of metal were used in subsequent experiments with the substance. The nearly anhydrous acid was prepared in 1809, and two years later the French physicist André-Marie Ampère suggested that it was a compound of hydrogen with an unknown element, analogous to chlorine, for which he suggested the name fluorine. Fluorspar was then recognized to be calcium fluoride.

The isolation of fluorine was for a long time one of the chief unsolved problems in inorganic chemistry, and it was not until 1886 that the French chemist Henri Moissan prepared the element by electrolyzing a solution of potassium hydrogen fluoride in hydrogen fluoride. He received the 1906 Nobel Prize for Chemistry for isolating fluorine. The difficulty in handling the element and its toxic properties contributed to the slow progress in fluorine chemistry. Indeed, up to the time of World War II the element appeared to be a laboratory curiosity. Then, however, the use of uranium hexafluoride in the separation of uranium isotopes, along with the development of organic fluorine compounds of industrial importance, made fluorine an industrial chemical of considerable use.

Occurrence and distribution

The fluorine-containing mineral fluorspar (fluorite, CaF2) has been used for centuries as a flux (cleansing agent) in various metallurgical processes. The name fluorspar is derived from the Latin fluere, “to flow.” The mineral subsequently proved to be a source of the element, which was accordingly named fluorine. The colourless, transparent crystals of fluorspar exhibit a bluish tinge when illuminated, and this property is accordingly known as fluorescence.

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Fluorine is found in nature only in the form of its chemical compounds, except for trace amounts of the free element in fluorspar that has been subjected to radiation from radium. Not a rare element, it makes up about 0.065 percent of Earth’s crust. The principal fluorine-containing minerals are (1) fluorspar, deposits of which occur in Illinois, Kentucky, Derbyshire, southern Germany, the south of France, and Russia and the chief source of fluorine, (2) cryolite (Na3AlF6), chiefly from Greenland, (3) fluoroapatite (Ca5[PO4]3[F,Cl]), widely distributed and containing variable amounts of fluorine and chlorine, (4) topaz (Al2SiO4[F,OH]2), the gemstone, and (5) lepidolite, a mica as well as a component of animal bones and teeth.

Physical and chemical properties

At room temperature fluorine is a faintly yellow gas with an irritating odour. Inhalation of the gas is dangerous. Upon cooling fluorine becomes a yellow liquid. There is only one stable isotope of the element, fluorine-19.

Fluorine Atomic Number 9 Meaning

Because fluorine is the most electronegative of the elements, atomic groupings rich in fluorine are often negatively charged. Methyl iodide (CH3I) and trifluoroiodomethane (CF3I) have different charge distributions as shown in the following formulas, in which the Greek symbol δ indicates a partial charge:

The first ionization energy of fluorine is very high (402 kilocalories per mole), giving a standard heat formation for the F+ cation of 420 kilocalories per mole.

The small size of the fluorine atom makes it possible to pack a relatively large number of fluorine atoms or ions around a given coordination centre (central atom) where it forms many stable complexes—for example, hexafluorosilicate (SiF6)2− and hexafluoroaluminate (AlF6)3−. Fluorine is the most powerfully oxidizing element. No other substance, therefore, is able to oxidize the fluoride anion to the free element, and for this reason the element is not found in the free state in nature. For more than 150 years, all chemical methods had failed to produce the element, success having been achieved only by the use of electrolytic methods. However, in 1986 American chemist Karl O. Christe reported the first chemical preparation of fluorine, where “chemical preparation” means a method that does not use techniques such as electrolysis, photolysis, and discharge or use fluorine itself in the synthesis of any of the starting materials. He used K2MnF6 and antimony pentafluoride (SbF5), both of which can be easily prepared from HF solutions.

Markdown in html table. The high oxidizing power of fluorine allows the element to produce the highest oxidation numbers possible in other elements, and many high oxidation state fluorides of elements are known for which there are no other corresponding halides—e.g., silver difluoride (AgF2), cobalt trifluoride (CoF3), rhenium heptafluoride (ReF7), bromine pentafluoride (BrF5), and iodine heptafluoride (IF7).

Fluorine (F2), composed of two fluorine atoms, combines with all other elements except helium and neon to form ionic or covalent fluorides. Some metals, such as nickel, are quickly covered by a fluoride layer, which prevents further attack of the metal by the element. Certain dry metals, such as mild steel, copper, aluminum, or Monel (a 66 percent nickel, 31.5 percent copper alloy), are not attacked by fluorine at ordinary temperatures. For work with fluorine at temperatures up to 600 °C (1,100 °F), Monel is suitable; sintered alumina is resistant up to 700 °C (1,300 °F). When lubricants are required, fluorocarbon oils are most suitable. Fluorine reacts violently with organic matter (such as rubber, wood, and cloth), and controlled fluorination of organic compounds by the action of elemental fluorine is only possible if special precautions are taken.

Quick Facts
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What are the quantum numbers for the 9th electron in flourine?

Fluorine Atomic Number 17

1 Answer


You know that fluorine has an atomic number equal to #9#, which means that the #'9th'# electron in an atom of fluorine is the last one added when 'constructing' the neutral atom of fluorine.

Fluorine is located in period#2# of the Periodic Table, which implies that the #'9th'# electron in fluorine is located on the second energy level.

Consequently, you can say that this electron will have a principal quantum number, #n#, which describes the energy level on which an electron is located in an atom, equal to

#n = 2#

Now, fluorine is located in group#17# of the Periodic Table, which means that fluorine is part of the #p#block.

This implies that the angular momentum quantum number, #l#, which describes the energy subshell in which the electron is located, will be equal to

Fluorine atomic number protons

#l = 1#

This is the case because you have

  • #l =0 -># describes the #s#subshell
  • #l = 1 -># describes the #p#subshell
  • #l = 2 -># describes the #d#subshell

and so on. Next, for the #p#subshell, the magnetic quantum number, #m_l#, which tells you the orientation of the orbital in which the electron is located, will be equal to

#m_l = {-1, 0, +1}#

By convention, you have

  • #m_l = -1 -># describes the #p_y#orbital#-># corresponds to groups #13# and #16#
  • #m_l = color(white)(-)0 -># describes the #p_z#orbital corresponds to groups #14# and #17#
  • #m_l = +1 -># descrbes the #p_x#orbital corresponds to groups #15# and #18#

Fluorine Group

Since the #'9th'# electron corresponds to group #17#, you can say that it will have

#m_l = 0#

This electron will be added to the #2p_z#orbital, which is the #p_z# orbital located on the second energy level.

Finally, the spin quantum number, #m_s#, which tells you the spin of the electron, can take two possible values

#m_s = {+1/2, - 1/2}#

Now, the #'9th'# electron will have

#m_s = -1/2#

because, by convention, electrons added to a half-filled orbital are assigned spin-down. The #p_z# orbital is half-filled because of Pauli's Exclusion Principle, which states that all three #p#orbitals must be half-filled before any of them can be filled completely.

You can thus say that the full quantum number set that describes the #'9th'# electron in an atom of fluorine will be

#n = 2, l =1, m_l = 0, m_s = -1/2#

Fluorine Atomic Number And Symbol

The electron is located on the second energy level, in the #2p#subshell, in the #2p_z#orbital, and has spin-down

Fluorine Atomic Number 9

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