On the periodic table element fluorine is classified as what?
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Name: fluorine \nSymbol: F \nAtomic number: 9 \nAtomic weight: 18.9984032 (5) \n\nGroup number: 17 \nGroup name: Halogen \nPeriod number: 2 \nBlock: p-block \n\nStandard state: gas at 298 K \nColour: pale yellow \nClassification: Non-metallic
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yes, it does because fluorine, being such an electronegative elements allows one of its lone pairs to become a bonding pair for another hydrogen to attach (other than its already used up bonding pair). and like the first quote HF has some of the strongest H-bonds due to the fluorine being one of most electronegative elements.
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Boron is a chemical element in the periodic table that has the symbol B and atomic number 5.
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The Periodic Table of Elements organizes all the elements known to man. There are certain characteristics of each elements that they are grouped by. For example, the last column on the right is called the "Noble Gasses" becase they are all gasses in their natural state, and they're atoms have every electron in each orbital making them the most stable elements.
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Selenium element is located in Group 6A of the periodic table. This in dicates that it has 6 electron in its valence or outermost shell. The Lewis dot structure of Selenium shoulde be written with Se surrounded by six dots. These six dots don't have to be an all four sides but if you do then that is the conventional way of doing it.
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Fluorine is the most electronegative element. That means it has very high capacity to attract shared pair of electrons towards itself. Due to its high elctron attracting nature it attracts most of the groups, atom having  spare electrons.\nit is more reactive than other elements in its gp because-\n\n-small size\n-less screening effect\n-high effective nuclear charge
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"Lithium (IPA: /ˈlɪθiəm/, from Greek: lithos: stone, because it was discovered in petalite) is a chemical element with the symbol Li and atomic number 3. Lithium is one of only four elements theorized to have been created in the first three minutes of the universe through a process called Big Bang nucleosynthesis. It is in group 1 of the periodic table, among the alkali metals and is the lightest solid element."
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The halogens can be found in column 17 of the Periodic Table.  They are called Group VII because they all have 7 electrons in their outer orbitals.\n\nThe lighter ones (Fluorine & Chlorine) are gases at room temperature.  Bromine is a liquid, while Iodine & Astatine are solids.  All tend to rapidly react by gaining an electron (they are good oxidizers).\n\nThe noble gases can be found in column 18 of the Periodic Table.  They are called Group VIII because they all have 8 electrons in their outer orbitals.\n\nHaving full outer orbitals, the noble gases usually do not react with other elements.  This is why they are sometimes called the Inert Gases.  Several compounds of Xenon and Fluorine and Oxygen have been make and studies, however.
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A fluoride ion is the ionic form of fluorine. Fluorides are organic and inorganic compounds containing the fluorine element. As a halogen, fluorine forms a monovalent ion (-1 charge). Fluoride forms a binary compound with another element or radical. Examples of common fluoride compounds include hydrofluoric acid (HF), and sodium fluoride (NaF).\n\n\nExamples\nsodium fluoride, NaF \ncarbon tetrafluoride, CF4 \noxygen difluoride, OF2 \nSee category for a bigger list.\n\n\nUses\nFluoride containing compounds are added to toothpaste, drinking water, perscribed treatments, and other commercially available oral hygiene products because they are believed to help strengthen the tooth enamel. Sodium fluoride and Sodium fluorophosphate (SMFP) are common additives.\n\nMany local water municipalities fluoridate their water supplies by adding fluoride in concentrations of less than 4 ppm. Originally, Sodium fluoride was used to fluoridate water; however, hexafluorosilicic acid (H2SiF6) and its salt (Na2SiF6) are more commonly used, especially in the United States.\n\nHydrofluoric acid is used in the etching of glass and other industrial applications, including integrated circuit manufacturing.\n\nFluoride ion has a very significant use in synthetic organic chemistry. The silicon-fluorine chemical bond is quite strong. Silyl ether protecting groups can be easily removed by the addition of fluoride ion. Sodium fluoride or tetra-butyl ammmonium fluoride (TBAF) are the most common reagents used.\n\n\nFluorides and human health\n\nHigher concentrations\nIn high concentrations fluoride compounds are toxic. A "certainly lethal dose" is estimated to be 32-64 fluoride mg per kilogram of body mass, although fatalities may occur in some individuals at doses as low as 5 mg/kg. Symptoms of acute toxicity (e.g. gastrointestinal distress) have been reported to occur at doses as low as 0.1 to 0.3 mg/kg.\n\nWhen ingested directly, fluoride compounds are readily absorbed by the intestines. Over time, the compound is excreted through the urine, and the half life for concentration of fluorine compounds is on an order of hours. Implied is that fluoride is taken out of circulation by the body and trace amounts bound in bone. Urine tests are a good indication of high exposure to fluoride compounds in the recent past.\n\nSkin or eye contact with many fluoride compounds (in high concentrations) is dangerous. In case of accidental swallowing, milk, calcium carbonate, or milk of magnesia is given to slow absorption. Eye or skin contact is treated by removing any contaminated clothing and flushing with water.\n\n\nLow concentrations\nFluoride is best known for its use in small quantities to help reduce Dental caries (cavity) frequency in teeth.\n\nFluoride compounds, usually calcium fluoride, are naturally found in low concentration in drinking water and some foods, like tea. The ocean itself has an averaged concentration of 1.3 ppm (parts per million). Fluoride ions replace hydroxide ions in calcium hydroxyapatite, Ca5[(PO4)3OH], in teeth, forming calcium fluoroapatite, Ca5[(PO4)3F], which is more chemically stable and dissolves at a pH of 4.5, compared to 5.5 pH for calcium hydroxyapatite. This is generally believed to lead to fewer cavities, since stronger acids are needed to attack the tooth enamel. In 1951, Joseph C. Muhler and Harry G. Day of Indiana University Bloomington reported their research results on stannous fluoride as a tooth decay preventive and the university first sold the technology to Procter & Gamble to use in Crest toothpaste.\n\nThe widely accepted adverse effect of low concentration fluoridation at this time is fluorosis. It is a condition caused by 'excessive' intake of fluorine compounds over an extended period of time, and can cause yellowing of teeth, hypothyroidism, or brittling of bones and teeth. The definition of 'excessive' in the context of fluorosis falls on the order of parts per million and is generally
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British chemist, John Newlands had the idea of arranging chemical elements in order of their relative atomic masses and he arranged his elements in columns. However, Russian chemist, Dmitri Mendeleev greatly improved on Newlands' idea and convinced other chemists to use it, so Mendeleev has been credited with the invention of the periodic table. Dmitri Mendeleev came up with his first version of the periodic table in 1864, since then more than 700 versions of the table have been proposed.\n\nNo chemistry textbook, classroom, lecture theatre or research laboratory is complete without a copy of the periodic table of the elements. Since the earliest days of chemistry, attempts have been made to arrange the known elements in ways that revealed similarities between them. However, it required the genius of Mendeleev to see that arranging elements into patterns was not enough; he realised that there was a natural plan in which each element has its allotted place, and this applies not only to the known elements but to some that were still undiscovered. Today we have the so-called long form of the table. This has emerged supreme from well over 100 designs that have been proposed since the time of Mendeleev. With the advantage of hindsight we can now see why this form of the table was bound to succeed.\n\nToday there are 111 elements recognised by IUPAC, and these are usually displayed in the form of a matrix called a periodic table. The term periodic came from the regular occurrence of certain chemical properties in the list of known elements when these are arranged in order of increasing relative mass. The common form, complete with the new group numbers (1-18) were finally agreed by the International Union of Pure Applied Chemistry, IUPAC, in 1985, after years of wrangling. In truly Parkinsonian fashion, this least important of changes has probably consumed the most effort!\n\nSince Antoine Lavoisier first defined a chemical element and drew up a table of 33 of them for his book 'Traité Elémentaire de Chimie' (Treatise on the Chemical Elements) published in 1789, there have been attempts to classify them. Lavoisier himself grouped them into four categories on the basis of their chemical properties: gases, nonmetals, metals and earths. In the first category he listed substances that we now know as oxides but which at the time had defeated all attempts at separation.\n\nThis desire to identify and classify elements continued in chemistry for another 80 years until Mendeleev stumbled upon the correct classification - the periodic table. Today the periodic table is securely based on the properties of atomic number of the nucleus and the electron energy levels which surround it. Both of these concepts postdate Mendeleev by several decades. He, however perceived them indirectly through the related properties of atomic weight and chemical valency and arrived at the periodic table in 1869.\n\nBecause atomic weight, relative atomic mass, is roughly proportional to atomic number, and because valency, which manifests itself in the chemical composition, is based on the outermost electrons of an atom, Mendeleev had chosen the two properties that in his day most nearly reflected the fundamental principles on which the table today is based. Consciously or subconsciously, he arrived at the idea that a table existed with positions that were to be occupied by the elements, rather than the other way round - that the known elements determined the arrangement of the table, as others imagined.\n\nThis being so, Mendeleev then put the 65 elements he knew into his table and at the same time pointed out the many unoccupied positions in the overall scheme. He took the further and much bolder step of predicting the properties of these missing elements. Moreover, the gap in atomic weights between cerium (140) and tantalum (182) suggested to him that a whole period of the table remained to be discovered. Later in the century many of these elements,
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Mercury and Bromine are the only liquids in the Periodic table. Francium, cesium, gallium, and rubidium are four elements that melt at temperatures slightly higher than room temperature.
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The representative elements are denoted with the last letter of "A" in the group names and there are eight major groups. Some of the more notable groupings are listed as follow: \n\nGroup IA (alkali metals) consists Li, Na, K, Rb, Cs, Fr \n\nGroup IIA (alkali earth metals) consists of Be, Mg, Ca, Sr, Ba, Ra. \n\nGroups IIIA, IVA, and VA elements are located close to the "staircase" that divides the metals on the left and the non-metals on the right. Most elements located along the "staircase" are classified as metalloids, e.g. B, Si, Ge, As, Sb, and Po. \n\nGroup VIA consists of O, S, Se, Te, and Po. \n\nGroup VIIA (halogens) consists of F, Cl, Br, I, and At. \n\nGroup VIIIA (rare gases) consists of He, Ne, Ar, Kr, Xe, and Rn.
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OVERSIMPLIFIED ANSWER\n\nActually, the periodic table was a stunning predictor of properties of elements. When it was first formulated, many of the elements we know of today had not been discovered, and so it contained many blank spots. Interestingly enough, it turns out that the groupings predicted properties of elements in groups. For instance, you could be reasonably certain that if 12 new halogens are found in the future, they will all have similar properties to the halogens that are grouped together today.\n\nHow do we know this? How were the elements grouped by properties before we knew what those properties were? Simply put, the periodic table is organized like this\n\nRight to left: number of electrons in the outermost orbital\n\nTop to bottom: atomic weight\n\nThis is oversimplified, but it works here. Electron configuration in the outer orbital is what determines an element's reactivity, the bulk of its chemical properties. Since there are 8 rows from left to right in the table, elements read from top to bottom all have the same number of electrons in their outer orbitals, so they all have similar properties.\n\nWhat's important to remember is that much of the periodic table was organized in its modern state BEFORE we knew this. Pretty nifty.
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1 Hydrogen 2 Helium 3 Lithium 4 Beryllium 5 Boron. 6 Carbon 7 Nitrogen 8 Oxygen 9 Fluorine 10 Neon
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In chemistry, a metal (Greek: Metallon) is an element that readily forms ions (cations) and has metallic bonds. Metals are sometimes described as a lattice of positive ions (cations) surrounded by a cloud of delocalized electrons. The metals are one of the three groups of elements as distinguished by their ionisation and bonding properties, along with the metalloids and nonmetals. On the periodic table, a diagonal line drawn from boron (B) to polonium (Po) separates the metals from the nonmetals. Elements on this line are metalloids, sometimes called semi-metals; elements to the lower left are metals; elements to the upper right are nonmetals.
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I would think your teacher is asking you about the way elements are grouped in the periodic table. You'll notice, for example, that gases are grouped together.\n\n Do a google on "classification of elements" -- there is a lot of stuff out there, and I'm sure it's also in your science text.
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Uranium is a chemical element in the periodic table that has the symbol U and atomic number 92. Heavy, silvery-white, toxic, metallic, naturally radioactive, pyrophoric, and teratogenic, uranium belongs to the actinide series and its isotope 235U is used as the fuel for nuclear reactors and the explosive material for nuclear weapons. Depleted uranium is used in incendiary projectile weapons. Uranium is commonly found in very small amounts in rocks, soil, water, plants, and animals (including humans).