जस्ता

Zinc, ₀₀Zn

किपा:Zinc-sample
Zinc
Appearance	वचुगु फिक्का ग्रे
Standard atomic weight Ar°(Zn)
	65.38±0.02 65.38±0.02 (abridged)
Zinc in the periodic table
- ↑ Zn ↓ Cd कपर ← zinc → ग्यालियम
Group	group 12
Period	period 4
Block	d-block
Electron configuration	[Ar] 3d10 4s2
Electrons per shell	2, 8, 18, 2
Physical properties
Phase at STP	solid
Melting point	692.68 K ​(419.53 °C, ​787.15 °F)
Boiling point	1180 K ​(907 °C, ​1665 °F)
Density (near r.t.)	7.14 g/cm3
when liquid (at m.p.)	6.57 g/cm3
Heat of fusion	7.32 kJ/mol
Heat of	123.6 kJ/mol
Molar heat capacity	25.390 J/(mol·K)
pressure P (Pa) 1 10 100 1 k 10 k 100 k at T (K) 610 670 750 852 990 (1185)
Atomic properties
Oxidation states	साधारण: +2 −2, 0,? +1
Electronegativity	Pauling scale: 1.65
energies	(more)
Atomic radius	empirical: 135 pm calculated: 142 pm
Covalent radius	131 pm
Van der Waals radius	139 pm
Color lines in a spectral range Spectral lines of zinc
Other properties
Natural occurrence	primordial
Crystal structure	​hexagonal
Thermal expansion	30.2 µm/(m⋅K) (at 25 °C)
Thermal conductivity	116 W/(m⋅K)
Electrical resistivity	59.0 n Ω⋅m (at 20 °C)
Magnetic ordering	diamagnetic
Young's modulus	108 GPa
Shear modulus	43 GPa
Bulk modulus	70 GPa
Speed of sound thin rod	(rolled) 3850 m/s (at r.t.)
Poisson ratio	0.25
Mohs hardness	2.5
Brinell hardness	412 MPa
CAS Number	7440-66-6
Isotopes of zinc

जिन्क धागु छगु रसायनिक तत्त्व ख। थुकिगु चिं Zn ख व एटोमिक ल्याखं ३० ख।

गुणत

जिन्क छगु मध्यम स्तरय् रियाक्सन याइगु वचुस्से-तुयुगु धातु ख। थ्व मोइस्ट वायुय् टार्निश जुइ व वायुय् वांगु जः वेक छ्वै, व थुकिलिं जिंक अक्साइड देकी। थ्व तत्त्व अम्ल, अल्काली व मेमेगु अधातु नाप रसायनिक स्वापू देकी। शुद्ध मजुगु जिंक डाइलुट अम्ल नाप रियाक्ट याना हाइड्रोजन पिकाइ। जिंकयागु छगु सामान्य अक्सिडेसन स्टेट +२ ख। १०० °से निसें २१० °से तक्क जिंक म्यालिएबल जुइ व अपुइक हे येक्व आकारे ढालेयाये छिं। २१० °से स्वया च्वे थ्व तत्त्व ब्रिटल जुइ व केकी बिले पल्भराइज्ड जुइ।

ज्या

जिन्क ४गु दक्ले अप्व छ्येलिगु धातु ख। थ्व स्वया अप्व छ्येलिगु धातुत न, एल्मुनियम, व कपर जक्क ख।

• जिंक स्टिलयात ग्याल्भेनाइज याना करोजन पंकेयात छ्येलि।
• जिंक is used to Parkerize steel to prevent rust and corrosion
• जिंक is used in alloys such as brass, nickelled silver, typewriter metal, various soldering formulas and German silver
• जिंक is the primary metal used in making American cents since 1982
• जिंक is used in die casting notably in the automobile industry
• जिंक is used as part of the containers of batteries. The most widespread such use is as the anode in alkaline batteries
• जिंक is used as the anode or fuel of the जिंक-air battery/fuel cell providing the basis of the theorised जिंक economy
• जिंक is used as a sacrificial anode on boats and ships that use cathodic protection to prevent corrosion of metals that are exposed to sea water
• जिंक is used in contemporary pipe organ building as a substitute for the classic lead/tin alloy in pipes sounding the lowest (pedal) tones, as it is tonally almost indistinguishable from lead/tin at those pitches, and has the added advantages of being much more economical and lighter in weight. Even the best organ builders use जिंक in this capacity.
• जिंक oxide is used as a white pigment in watercolours or paints, and as an activator in the rubber industry. As an over-the-counter ointment, it is applied as a thin coating on the exposed skin of the face or nose to prevent dehydration of the area of skin. It can protect against sunburn in the summer and windburn in the winter. Applied thinly to a baby's diaper area (perineum) with each diaper change, it can protect against rash. As determined in the Age-Related Eye Disease Study, it is part of an effective treatment for age-related macular degeneration in some cases
• जिंक chloride is used as a deodorant and can also be used as a wood preservative
• जिंक sulfide is used in luminescent pigments such as on the hands of clocks and other items that glow in the dark.
• जिंक methyl (Zn(CH₃)₂) is used in a number of organic syntheses.
• जिंक stearate is a lubricative plastic additive.
• Lotions made of calamine, a mix of Zn-(hydroxy-)carbonates and silicates, are used to treat skin rash.
• जिंक metal is included in most single tablet over-the-counter daily vitamin and mineral supplements. It is believed to possess anti-oxidant properties, which protect against premature aging of the skin and muscles of the body. In larger amounts, taken as जिंक alone in other proprietaries, it is believed by some to speed up the healing process after an injury. Preparations include जिंक acetate and जिंक gluconate.
• जिंक gluconate glycine and जिंक acetate are also used in throat lozenges or tablets to reduce the duration and the severity of cold symptoms.

Abundance

See also: Zinc minerals

Zinc is the 23rd most abundant element in the Earth's crust. The most heavily mined ores (sphalerite) tend to contain roughly 10% iron as well as 40–50% zinc. Minerals from which zinc is extracted include sphalerite (zinc sulfide), smithsonite (zinc carbonate), hemimorphite (zinc silicate), and franklinite (a zinc spinel).

The earth has been estimated to have 46 years supply of zinc.

Zinc mining and processing

किपा:Zinc (mined)2.PNG

Zinc output in 2005

There are zinc mines throughout the world, with the largest producers being China, Australia and Peru. In 2005, China produced almost one-fourth of the global zinc output, reports the British Geological Survey. Mines and refineries in Europe include Umicore in Belgium, Tara, Galmoy and Lisheen in Ireland, and Zinkgruvan in Sweden. Zinc metal is produced using extractive metallurgy. Zinc sulfide (sphalerite) minerals are concentrated using the froth flotation method and then usually roasted using pyrometallurgy to oxidise the zinc sulfide to zinc oxide. The zinc oxide is leached in several stages of increasingly stronger sulfuric acid (H₂SO₄). Iron is usually rejected as Jarosite or goethite, removing other impurities at the same time. The final purification uses zinc dust to remove copper, cadmium and cobalt. The metal is then extracted from the solution by electrowinning as cathodic deposits. Zinc cathodes can be directly cast or alloyed with aluminium.

Electrolyte solutions must be very pure for electrowinning to be at all efficient. Impurities can change the decomposition voltage enough to where the electrolysis cell produces largely hydrogen gas rather than zinc metal.

There are two common processes for electrowinning the metal, the low current density process, and the Tainton high current density process. The former uses a 10% sulfuric acid solution as the electolyte, with current density of 270–325 amperes per square meter. The latter uses 22-28% sulfuric acid solution as the electrolyte with current density of about 1000 amperes per square meter. The latter gives better purity and has higher production capacity per volume of electrolyte, but has the disadvantage of running hotter and being more corrosive to the vessel in which it is done. In either of the electrolytic processes, each metric ton of zinc production expends about 3900 kW·h (14 MJ) of electric power.

There are also several pyrometallurgical processes that reduce zinc oxide using carbon, then distill the metallic zinc from the resulting mix in an atmosphere of carbon monoxide. These include the Belgian-type horizontal-retort process, the New Jersey Zinc continuous vertical-retort process, and the St. Joseph Lead Company's electrothermal process. The Belgian process requires redistillation to remove impurities of lead, cadmium, iron, copper, and arsenic. The New Jersey process employs a fractionating column, which is absent in the Belgian process, that separates the individual impurities, where they can be sold as byproducts. The St. Joseph Lead Company process heats the zinc oxide/coke mixture by passing an electric current through it rather than by coal or gas fire.

Another pyrometallurgical process is flash smelting. Then zinc oxide is obtained, usually producing zinc of lesser quality than the hydrometallurgical process. Zinc oxide treatment has much fewer applications, but high grade deposits have been successful in producing zinc from zinc oxides and zinc carbonates using hydrometallurgy.

अलोयत

The most widely used alloy of zinc is brass, in which copper is alloyed with anywhere from 9% to 45% zinc, depending upon the type of brass, along with much smaller amounts of lead and tin. Alloys of 85–88% zinc, 4–10% copper, and 2–8% aluminum find limited use in certain types of machine bearings. Alloys of primarily zinc with small amounts of copper, aluminum, and magnesium are useful in die-casting. Similar alloys with the addition of a small amount of lead can be cold-rolled into sheets. An alloy of 96% zinc and 4% aluminum is used to make stamping dies for low production run applications where ferrous metal dies would be too expensive.

कम्पाउन्डत

See also: Zinc compounds

Zinc oxide is perhaps the best known and most widely used zinc compound, as it makes a good base for white pigments in paint. It also finds industrial use in the rubber industry, and is sold as opaque sunscreen. A variety of other zinc compounds find use industrially, such as zinc chloride (in deodorants), zinc pyrithione (anti-dandruff shampoos), zinc sulfide (in luminescent paints), and zinc methyl or zinc diethyl in the organic laboratory. Roughly one quarter of all zinc output is consumed in the form of zinc compounds.

आइसोटोपत

Naturally occurring zinc is composed of the 5 stable isotopes ⁶⁴Zn, ⁶⁶Zn, ⁶⁷Zn, ⁶⁸Zn, and ⁷⁰Zn with ⁶⁴Zn being the most abundant (48.6% natural abundance). Twenty-one radioisotopes have been characterised with the most abundant and stable being ⁶⁵Zn with a half-life of 244.26 days, and ⁷²Zn with a half-life of 46.5 hours. All of the remaining radioactive isotopes have half-lives that are less than 14 hours and the majority of these have half lives that are less than 1 second. This element also has 4 meta states.

Zinc has been proposed as a "salting" material for nuclear weapons (cobalt is another, better-known salting material). A jacket of isotopically enriched ⁶⁴Zn, irradiated by the intense high-energy neutron flux from an exploding thermonuclear weapon, would transmute into the radioactive isotope Zn-65 with a half-life of 244 days and produce approximately 2.27 MeV of gamma radiation, significantly increasing the radioactivity of the weapon's fallout for several days. Such a weapon is not known to have ever been built, tested, or used.

Precautions

Metallic zinc is not considered to be toxic, but free zinc ions in solution (like copper or iron ions) are highly toxic. There is also a condition called zinc shakes or zinc chills (see metal fume fever) that can be induced by the inhalation of freshly formed zinc oxide formed during the welding of galvanized materials. Excessive intake of zinc can promote deficiency in other dietary minerals.

लिधंसा

• Los Alamos National Laboratory - Zinc
• WebElements.com – Zinc

पिनेयागु स्वापूत

• Indian Contribution
• History & Etymology of Zinc
• Statistics and Information from the U.S. Geological Survey
• Reducing Agents > Zinc
• American Zinc Association Information about the uses and properties of zinc.