ویژگیهای فلزات، شبهفلزات و نافلزات: تفاوت میان نسخهها
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=== Details ===
==Comparison of properties==
===Overview===
<!-- OVERVIEW TABLE -->
{{Metals-metalloids-nonmetals: compare, overview}}
{{nowrap|The characteristic}} properties of metals and nonmetals are quite distinct, as shown in the table below. Metalloids, straddling the [[dividing line between metals and nonmetals|metal-nonmetal border]], are mostly distinct from either, but in a few properties resemble one or the other, as shown in the shading of the metalloid column below and summarized in the small table at the top of this section.
Authors differ in where they divide metals from nonmetals and in whether they recognize an intermediate [[metalloid]] category. Some authors count metalloids as nonmetals with weakly nonmetallic properties.{{#tag:ref|For example:
*Brinkley<ref>[[#Brinkley1945|Brinkley 1945, p. 378]]</ref> writes that boron has weakly nonmetallic properties.
*Glinka<ref>[[#Glinka1965|Glinka 1965, p. 88]]</ref> describes silicon as a weak nonmetal.
*Eby et al.<ref>[[#Eby1943|Eby et al. 1943, p. 404]]</ref> discuss the weak chemical behaviour of the elements close to the metal-nonmetal borderline.
*Booth and Bloom<ref>[[#Booth1972|Booth & Bloom 1972, p. 426]]</ref> say "A period represents a stepwise change from elements strongly metallic to weakly metallic to weakly nonmetallic to strongly nonmetallic, and then, at the end, to an abrupt cessation of almost all chemical properties ...".
*Cox<ref name=Cox /> notes "nonmetallic elements close to the metallic borderline ([[silicon|Si]], [[germanium|Ge]], [[arsenic|As]], [[antimony|Sb]], [[selenium|Se]], [[tellurium|Te]]) show less tendency to anionic behaviour and are sometimes called metalloids."|group=n}} Others count some of the metalloids as [[post-transition metal]]s.{{#tag:ref|See, for example, Huheey, Keiter & Keiter<ref>[[#HuheeyK|Huheey, Keiter & Keiter 1993, p. 28]]</ref> who classify Ge and Sb as post-transition metals.|group=n}}
{{clear}}
===Details===
<!-- DETAIL TABLE (big) -->
{{Metals-metalloids-nonmetals: compare, details}}
==Anomalous properties==
{{Quote box
| quote = There were exceptions…in the periodic table, anomalies too—some of them profound. Why, for example, was manganese such a bad conductor of electricity, when the elements on either side of it were reasonably good conductors? Why was strong magnetism confined to the iron metals? And yet these exceptions, I was somehow convinced, reflected special additional mechanisms at work…
| salign=right| source = Oliver Sacks<br>[[#Sacks|''Uncle Tungsten'']] (2001, p. 204)
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Within each category, elements can be found with one or two properties very different from the expected norm, or that are otherwise notable.
===Metals===
<!-- {{Periodic table (micro)|title=|mark=Na,K,Rb,Cs,Ba,Pt,Au}} -->'''[[Sodium]]''', '''[[potassium]]''', '''[[rubidium]]''', '''[[caesium]]''', '''[[barium]]''', '''[[platinum]]''', '''[[gold]]'''
:*The common notions that "alkali metal ions (group 1A) always have a +1 charge"<ref>[[#Brownet|Brown et al. 2009, p. 137]]</ref> and that "transition elements do not form anions"<ref>[[#Brescia1975|Bresica et al. 1975, p. 137]]</ref> are [[textbook]] errors. The synthesis of a crystalline salt of the sodium anion Na<sup>−</sup> was reported in 1974. Since then further compounds ("[[alkalide]]s") containing anions of all other [[alkali metal]]s except [[lithium|Li]] and [[francium|Fr]], as well as that of [[barium|Ba]], have been prepared. In 1943, Sommer reported the preparation of the yellow transparent compound [[Caesium auride|CsAu]]. This was subsequently shown to consist of caesium cations (Cs<sup>+</sup>) and auride anions (Au<sup>−</sup>) although it was some years before this conclusion was accepted. Several other aurides (KAu, RbAu) have since been synthesized, as well as the red transparent compound Cs<sub>2</sub>Pt which was found to contain Cs<sup>+</sup> and Pt<sup>2−</sup> ions.<ref>[[#Jansen2005|Jansen 2005]]</ref>
<!-- {{Periodic table (micro)|title=|mark=Mn}} -->'''[[Manganese]]'''
:*Well-behaved metals have crystal structures featuring [[unit cell]]s with up to four atoms. Manganese has a complex crystal structure with a 58-atom unit cell, effectively four different atomic radii, and four different [[coordination number]]s (10, 11, 12 and 16). It has been described as resembling "a quaternary [[intermetallic compound]] with four Mn atom types bonding as if they were different elements."<ref name=R>[[#Russell2005|Russell & Lee 2005, p. 246]]</ref> The half-filled ''3d'' shell of manganese appears to be the cause of the complexity. This confers a large [[magnetic moment]] on each atom. Below 727 °C, a unit cell of 58 spatially diverse atoms represents the energetically lowest way of achieving a zero net magnetic moment.<ref>[[#Russell2005|Russell & Lee 2005, p. 244–5]]</ref> The crystal structure of manganese makes it a hard and brittle metal, with low electrical and thermal conductivity. At higher temperatures "greater lattice vibrations nullify magnetic effects"<ref name=R/> and manganese adopts less complex structures.<ref>[[#Donohoe|Donohoe 1982, pp. 191–196]]; [[#Russell2005|Russell & Lee 2005, pp. 244–247]]</ref>
<!-- {{Periodic table (micro)|title=|mark=Fe,Co,Ni,Gd,Tb,Dy,Ho,Er,Tm}} -->'''[[Iron]]''', '''[[cobalt]]''', '''[[nickel]]''', '''[[gadolinium]]''', '''[[terbium]]''', '''[[dysprosium]]''', '''[[holmium]]''', '''[[erbium]]''', '''[[thulium]]'''
:*The only elements strongly attracted to magnets are iron, cobalt, and nickel at room temperature, gadolinium just below, and terbium, dysprosium, holmium, erbium, and thulium at ultra cold temperatures (below −54 °C, −185 °C, −254 °C, −254 °C, and −241 °C respectively).<ref>[[#Jackson2000|Jackson 2000]]</ref>
<!-- {{Periodic table (micro)|title=|mark=Ir}} -->'''[[Iridium]]'''
:*The only element encountered with an oxidation state of +9 is iridium, in the [IrO<sub>4</sub>]<sup>+</sup> cation. Other than this, the highest known oxidation state is +8, in [[ruthenium|Ru]], [[xenon|Xe]], [[osmium|Os]], [[iridium|Ir]], and [[hassium|Hs]].<ref>[[#Stoye|Stoye 2014]]</ref>
<!-- {{Periodic table (micro)|title=|mark=Au}} -->'''[[Gold]]'''
:*The [[malleable|malleability]] of gold is extraordinary: a fist sized lump can be hammered and separated into one million paper back sized sheets, each 10 [[nanometer|nm]] thick,{{citation needed|date=April 2015}} 1600 times thinner than regular kitchen aluminium foil (0.016 mm thick).{{citation needed|date=April 2015}} <!--Copied the info from [[aluminium foil]], but I couldn't find the reference-->
<!-- {{Periodic table (micro)|title=|mark=Hg}} -->'''[[Mercury (element)|Mercury]]
#Bricks and bowling balls will float on the surface of mercury thanks to it having a density 13.5 times that of water. Equally, a solid mercury bowling ball would weigh around 50 pounds and, if it could be kept cold enough, would float on the surface of liquid [[gold]].{{citation needed|date=April 2015}}
#The only metal having an ionisation energy higher than some nonmetals ([[sulfur]] and [[selenium]]) is mercury.{{citation needed|date=April 2015}}
#Mercury and its compounds have a reputation for toxicity but on a scale of 1 to 10, [[dimethylmercury]] ((CH<sub>3</sub>)<sub>2</sub>Hg) (abbr. DMM), a volatile colourless liquid, has been described as a 15. It is so dangerous that scientists have been encouraged to use less toxic mercury compounds wherever possible. In 1997, [[Karen Wetterhahn]], a professor of chemistry specialising in toxic metal exposure, died of mercury poisoning ten months after a few drops of DMM landed on her "protective" latex gloves. Although Wetterhahn had been following the then published procedures for handling this compound, it passed through her gloves and skin within seconds. It is now known that DMM is exceptionally permeable to (ordinary) gloves, skin and tissues. And its toxicity is such that less than one-tenth of a ml applied to the skin will be seriously toxic.<ref>[[#Witt|Witt 1991]]; [[#Endicott|Endicott 1998]]</ref>
<!-- {{Periodic table (micro)|title=|mark=Pb}} -->'''[[Lead]]'''
:*The expression, to "[[:wikt:go down like a lead balloon|go down like a lead balloon]]" is anchored in the common view of lead as a dense, heavy metal—being nearly as dense as mercury. However, it is possible to construct a balloon made of lead foil, filled with a [[helium]] and air mixture, which will float and be buoyant enough to carry a small load.{{citation needed|date=April 2015}}
<!-- {{Periodic table (micro)|title=|mark=Bi}} -->'''[[Bismuth]]'''
:*Bismuth has the longest [[half-life]] of any naturally occurring element; its only [[primordial isotope]], [[bismuth-209]], was found in 2003 to be slightly [[radioactive]], decaying via [[alpha decay]] with a half-life more than a billion times the estimated [[age of the universe]]. Prior to this discovery, bismuth-209 was thought to be the heaviest naturally occurring stable isotope;<ref>[[#Dumé2003|Dumé 2003]]</ref> this distinction now belongs to lead-208.
<!-- {{Periodic table (micro)|title=|mark=U}} -->'''[[Uranium]]'''
:*The only element with a naturally occurring isotope capable of undergoing nuclear fission is uranium.<ref>[[#Alvarez|Benedict et al. 1946, p. 19]]</ref> The capacity of [[uranium-235]] to undergo fission was first suggested (and ignored) in 1934, and subsequently discovered in 1938.{{#tag:ref| In 1934, a team led by [[Enrico Fermi]] postulated that [[transuranium elements|transuranic elements]] may have been produced as a result of bombarding uranium with neutrons, a finding which was widely accepted for a few years. In the same year [[Ida Noddack]], a German scientist and subsequently a three-time [[Nobel prize]] nominee, criticised this assumption, writing "It is conceivable that the nucleus ''breaks up into several large fragments'', which would of course be isotopes of known elements but would not be neighbors of the irradiated element."<ref>[[#Ida|Noddack 1934, p. 653]]</ref>[emphasis added] In this, Noddak defied the understanding of the time without offering experimental proof or theoretical basis, but nevertheless presaged what would be known a few years later as nuclear fission. Her paper was generally ignored as, in 1925, she and two colleagues claimed to have discovered element 43, then proposed to be called masurium (later discovered in 1936 by Perrier and Segrè, and named [[technetium]]). Had Ida Noddack's paper been accepted it is likely that Germany would have had an [[atomic bomb]] and, 'the history of the world would have been [very] different.'<ref>[[#Sacks|Sacks 2001, p. 205]]: 'This story was told by Glenn Seaborg when he was presenting his recollections at a conference in November 1997.'</ref>|group=n}}
<!-- {{Periodic table (micro)|title=|mark=Pu}} -->'''[[Plutonium]]'''
:*It is a commonly held belief that metals reduce their electrical conductivity when heated. Plutonium increases its electrical conductivity when heated in the temperature range of around –175 to +125 °C.{{citation needed|date=April 2015}}
===Metalloids===
<!-- {{Periodic table (micro)|title=|mark=B}} -->'''[[Boron]]'''
:*Boron is the only element with a partially disordered structure in its most thermodynamically stable crystalline form.<ref>[[#Dalhouse|Dalhouse University 2015]]; [[#White|White et al. 2015]]</ref>
{{clear}}
<!-- {{Periodic table (micro)|title=|mark=B,Sb}}-->'''[[Boron]]''', '''[[antimony]]'''
:*These elements are record holders within the field of [[superacid]] chemistry. For seven decades, [[fluorosulfonic acid]] HSO<sub>3</sub>F and [[trifluoromethanesulfonic acid]] CF<sub>3</sub>SO<sub>3</sub>H were the strongest known acids that could be isolated as single compounds. Both are about a thousand times more acidic than pure [[sulfuric acid]]. In 2004, a boron compound broke this record by a thousand fold with the synthesis of [[carborane acid]] H(CHB<sub>11</sub>Cl<sub>11</sub>). Another metalloid, antimony, features in the strongest known acid, a mixture 10 billion times stronger than carborane acid. This is [[fluoroantimonic acid]] H<sub>2</sub>F[SbF<sub>6</sub>], a mixture of [[antimony pentafluoride]] SbF<sub>5</sub> and [[hydrofluoric acid]] HF.{{citation needed|date=April 2015}}
<!-- {{Periodic table (micro)|title=|mark=Si}} -->'''[[Silicon]]'''
#The thermal conductivity of silicon is better than that of most metals.{{citation needed|date=April 2015}}
#A sponge-like [[Porous silicon|porous]] form of silicon (p-Si) is typically prepared by the electrochemical etching of silicon wafers in a [[hydrofluoric acid]] solution.<ref name="DuPlessis">[[#DuPlessis|DuPlessis 2007, p. 133]]</ref> Flakes of p-Si sometimes appear red;<ref>[[#Gösele|Gösele & Lehmann 1994, p. 19]]</ref> it has a band gap of 1.97–2.1 eV.<ref>[[#Chen|Chen, Lee & Bosman 1994]]</ref> The many tiny pores in porous silicon give it an enormous internal surface area, up to 1,000 m<sup>2</sup>/cm<sup>3</sup>.<ref name="Kovalev">[[#Kovalev|Kovalev et al. 2001, p. 068301-1]]</ref> When exposed to an [[oxidant]],<ref>[[#Mikulec|Mikulec, Kirtland & Sailor 2002]]</ref> especially a liquid oxidant,<ref name="Kovalev"/> the high surface-area to volume ratio of p-Si creates a very efficient burn, accompanied by nano-explosions,<ref name=DuPlessis/> and sometimes by [[ball lightning|ball-lightning]]-like plasmoids with, for example, a diameter of 0.1–0.8 m, a velocity of up to 0.5 m/s and a lifetime of up to 1s.<ref>[[#Bychkov|Bychkov 2012, pp. 20–21]]; see also [[#Lazaruk|Lazaruk et al. 2007]]</ref> The first ever spectrographic analysis of a ball lightning event (in 2012) revealed the presence of silicon, iron and calcium, these elements also being present in the soil.<ref>[[#Slezak|Slezak 2014]]</ref>
<!-- {{Periodic table (micro)|title=|mark=As}} -->'''[[Arsenic]]'''
:*Metals are said to be [[melting|fusible]], resulting in some confusion in old chemistry as to whether arsenic was a true metal, or a nonmetal, or something in between. It [[sublimation (phase transition)|sublimes]] rather than melts at standard [[atmospheric pressure]], like the nonmetals [[carbon]] and [[red phosphorus]].{{citation needed|date=April 2015}}
<!-- {{Periodic table (micro)|title=|mark=Sb}} -->'''[[Antimony]]'''
:*A high-energy explosive form of antimony was first obtained in 1858. It is prepared by the electrolysis of any of the heavier antimony trihalides (SbCl<sub>3</sub>, SbBr<sub>3</sub>, SbI<sub>3</sub>) in a hydrochloric acid solution at low temperature. It comprises amorphous antimony with some occluded antimony trihalide (7–20% in the case of the [[antimony trichloride|trichloride]]). When scratched, struck, powdered or heated quickly to 200 °C, it "flares up, emits sparks and is converted explosively into the lower-energy, crystalline grey antimony."<ref>[[#Wiberg2001|Wiberg 2001, p. 758]]; see also [[#Fraden|Fraden 1951]]</ref>
===Nonmetals===
<!-- {{Periodic table (micro)|title=|mark=H}} -->'''[[Hydrogen]]'''
#[[Water]] (H<sub>2</sub>O), a well known [[oxide]] of hydrogen, is a spectacular anomaly.<ref>[[#Sacks|Sacks 2001, p. 204]]</ref> Extrapolating from the heavier [[hydrogen chalcogenide]]s, namely [[hydrogen sulfide]] H<sub>2</sub>S, [[hydrogen selenide]] H<sub>2</sub>Se, and [[hydrogen telluride]] H<sub>2</sub>Te, water should be "a foul-smelling, poisonous, inflammable gas…condensing to a nasty liquid [at] around –100° C". Instead, due to [[hydrogen bonding]], water is "stable, potable, odorless, benign, and…indispensable to life".<ref>[[#Sacks|Sacks 2001, pp. 204–205]]</ref>
#Less well known of the oxides of hydrogen is the [[hydrogen trioxide|trioxide]], H<sub>2</sub>O<sub>3</sub>. [[Marcellin Berthelot|Berthelot]] proposed the existence of this oxide in 1880 but his suggestion was soon forgotten as there was no way of testing it using the technology of the time.<ref name=Cerkovnik>[[#Cerkovnik|Cerkovnik & Plesničar 2013, p. 7930]]</ref> Hydrogen trioxide was prepared in 1994 by replacing the oxygen used in the industrial process for making hydrogen peroxide, with [[ozone]]. The yield is about 40 per cent, at –78 °C; above around –40 °C it decomposes into water and oxygen.<ref>[[#Emsley1994|Emsley 1994, p. 1910]]</ref> Derivatives of hydrogen trioxide, such as {{nowrap|F<sub>3</sub>C–O–O–O–CF<sub>3</sub>}} ("bis(trifluoromethyl) trioxide") are known; these are [[metastable]] at room temperature.<ref name=WibergD/> [[Mendeleev]] went a step further, in 1895, and proposed the existence of [[hydrogen tetroxide]] {{nowrap|HO–O–O–OH}} as a transient intermediate in the decomposition of hydrogen peroxide;<ref name=Cerkovnik/> this was prepared and characterised in 1974, using a matrix isolation technique.{{citation needed|date=January 2015}} [[Alkali metal]] [[ozonide]] salts of the unknown [[hydrogen ozonide]] (HO<sub>3</sub>) are also known; these have the formula MO<sub>3</sub>.<ref name=WibergD>[[#Wiberg2001|Wiberg 2001, p. 497]]</ref>
<!-- {{Periodic table (micro)|title=|mark=He}} -->'''[[Helium]]'''
#At temperatures below 0.3 and 0.8 K respectively, [[helium-3]] and [[helium-4]] each have a negative [[enthalpy of fusion]]. This means that, at the appropriate constant pressures, these substances freeze with the ''addition'' of heat.{{citation needed|date=April 2015}}
#Until 1999 helium was thought to be too small to form a cage [[clathrate]]—a compound in which a guest atom or molecule is encapsulated in a cage formed by a host molecule—at atmospheric pressure. In that year the synthesis of microgram quantities of [[Dodecahedrane#Encapsulating atoms in dodecahedrane|He@C<sub>20</sub>H<sub>20</sub>]] represented the first such helium clathrate and (what was described as) the world's smallest helium balloon.<ref>[[#Cross|Cross, Saunders & Prinzbach]]; [[#Horst|Chemistry Views 2015]]</ref>
<!-- {{Periodic table (micro)|title=|mark=C}} -->'''[[Carbon]]'''
#Graphite is the most electrically conductive nonmetal, better than some metals.{{citation needed|date=April 2015}}
#[[Diamond]] is the best natural conductor of heat; it even feels cold to the touch. Its thermal conductivity (2,200 W/m•K) is five times greater than the most conductive metal ([[silver|Ag]] at 429); 300 times higher than the least conductive metal ([[plutonium|Pu]] at 6.74); and nearly 4,000 times that of water (0.58) and 100,000 times that of air (0.0224). This high thermal conductivity is used by jewelers and gemologists to separate diamonds from imitations.{{citation needed|date=April 2015}}
#Graphene [[aerogel]], produced in 2012 by freeze-drying a solution of [[carbon nanotube]]s and [[graphite oxide]] sheets and chemically removing oxygen, is seven times lighter than air, and ten per cent lighter than helium. It is the lightest solid known (0.16 mg/cm<sup>3</sup>), conductive and elastic.<ref>[[#Sun|Sun, Xu & Gao 2013]]; [[#Anthony|Anthony 2013]]</ref>
<!-- {{Periodic table (micro)|title=|mark=P}} -->'''[[Phosphorus]]'''
:*The least stable and most reactive form of phosphorus is the [[Allotropes of phosphorus#White phosphorus|white]] [[allotrope]]. It is a hazardous, highly flammable and toxic substance, spontaneously igniting in air and producing [[phosphoric acid]] residue. It is therefore normally stored under water. White phosphorus is also the most common, industrially important, and easily reproducible allotrope, and for these reasons is regarded as the [[standard state]] of phosphorus. The most stable form is the [[Allotropes of phosphorus#Black phosphorus|black allotrope]], which is a metallic looking, brittle and relatively non-reactive semiconductor (unlike the white allotrope, which has a white or yellowish appearance, is pliable, highly reactive and a semiconductor). When assessing periodicity in the physical properties of the elements it needs to be borne in mind that the quoted properties of phosphorus tend to be those of its least stable form rather than, as is the case with all other elements, the most stable form.{{citation needed|date=April 2015}}
<!-- {{Periodic table (micro)|title=|mark=I}} -->'''[[Iodine]]'''
:*The mildest of the [[halogen]]s, iodine is the active ingredient in [[tincture of iodine]], a disinfectant. This can be found in household medicine cabinets or emergency survival kits. Tincture of iodine will rapidly dissolve gold,<ref>[[#Nakao|Nakao 1992]]</ref> a task ordinarily requiring the use of [[aqua regia]] (a highly corrosive mixture of [[nitric acid|nitric]] and [[hydrochloric acid]]s).{{citation needed|date=April 2015}}
==Notes==
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