What kind of pure substance is zinc

Represented in the periodic table as Zn, zinc is a transition metal, grouped with cadmium and mercury. With the middling atomic number 30, it has five stable isotopes of atomic weight from the dominant zinc 64 to zinc 70, plus an extra 25 radioisotopes. Because of its hazy origins, it's difficult to pin down one person as the discoverer of the element. Although it seems to have been refined in India as early as the twelfth century, the earliest specific claim to have produced the metal was back in , and a process for extracting zinc from its oxide was patented in the UK in by metal trader William Champion.

But it is usually the German chemist Andreas Marggraf who wins the laurels as 'discoverer' for his experiment isolating zinc. Although zinc's history is more than a little hazy, there's no doubting its usefulness. You've only got to look at a galvanized metal roof or bucket to see zinc at work.

Galvanization is named after Luigi Galvani, the man who made frog legs twitch with electric current, but galvanization has nothing to do with electrical showmanship.

In fact electricity's role is surprisingly subtle. The most common form of galvanization is hot dip galvanization, where iron or steel is slid through a bath of liquid zinc at around degrees Celsius, forty degrees above its melting point. The coating prevents the object treated from rusting. Initially the zinc simply stops the air getting to the iron, but later the zinc corrodes in preference to iron in an electro-chemical process, acting as a so-called sacrificial anode.

This is where the 'galvanic' part of the name comes in. Some galvanization is more literally electrical - car bodies, for example, are electroplated with zinc to apply a thin, even layer. Zinc's electrical capabilities also extend to the most popular batteries. A traditional dry cell has an outer zinc casing acting as the anode confusingly the anode, usually thought of as positive, is the negative end of a battery , while a carbon rod provides the cathode, the positive electrode.

In the longer lasting alkaline batteries, the anode is formed from powdered zinc giving more surface area for reaction , while the cathode is made up of the compound manganese dioxide.

But the most visible example of zinc at work doesn't give any indication of this greyish metal - instead it's in an alloy that mixes the sheen of gold with the common touch.

When molten zinc and copper are mixed together, the result is bold as brass. In fact, it is brass. Everything from door fixings to decorative plaques for horse collars have been made in this flexible alloy.

Any orchestra would be much poorer without its brass instruments. It's even likely to turn up in the zips on your clothing. Well-polished brass has a pleasant glow - but our most intimate contact with zinc, or to be precise zinc oxide - often comes when dealing with the unwanted glow of sunburn. When I was young and there was little in the way of sun block, sunburned skin would be lavishly coated in soothing pink calamine lotion.

The primary ingredient of this is zinc oxide, which is white - it's small amounts of iron oxide that give it that colour. Even now, though, when we can avoid the need for calamine, zinc oxide plays its part.

Called Chinese white when it's used in paints, zinc oxide is a good absorber of ultraviolet light - so sun block often contains a suspension of tiny zinc oxide particles - as does most mineral-based makeup. And that's just the start for this versatile oxide.

You'll find it used in fire retardants and foods - where it fortifies the likes of breakfast cereals - in glass and ceramics, in glues and rubber. That surprise appearance on the breakfast table reflects another important side to zinc. We need it to stay healthy. It's one of the trace elements, nutrients that our bodies need in small quantities to keep functioning.

It's often present in vitamin supplements, though most of us get plenty from meat and eggs. The zinc ends up in various proteins, particularly in enzymes involved in the development of the body, digestion and fertility.

A shortage of zinc in the diet can lead to delayed healing, skin irritation and loss of the sense of taste, and encourages many chronic illnesses. With zinc also appearing in anti-dandruff shampoos in the form of zinc pyrithione and in underarm deodorants as zinc chloride, this is an element that even makes us more attractive to the opposite sex. Zinc is a hidden star. We're rarely aware of it, unlike its flashier neighbours in the period table, but zinc is a workhorse element that helps us all.

Bristolbased science writer Brian Clegg with the onomatopoeic element, zinc. Next week, what's lurking in your basement. The first reports of problems associated with radon gas in domestic buildings was in the United States in , when an employee at a nuclear power plant began setting off the radiation detector alarms on his way into work.

The problem was eventually traced to his home, where the level of radon gas in the basement was found to be abnormally high. But where was it coming from and what was the risk to his health.

Katherine Holt will be here with all of the answers and the rest of the Radon story on next week's Chemistry in its Element, I do hope you can join us. I'm Chris Smith, thank you for listening, and goodbye. Chemistry in its element is brought to you by the Royal Society of Chemistry and produced by thenakedscientists. There's more information and other episodes of Chemistry in its element on our website at chemistryworld.

Click here to view videos about Zinc. View videos about. Help Text. Learn Chemistry : Your single route to hundreds of free-to-access chemistry teaching resources. We hope that you enjoy your visit to this Site. We welcome your feedback. Data W. Haynes, ed. Version 1. Coursey, D. Schwab, J. Tsai, and R. Dragoset, Atomic Weights and Isotopic Compositions version 4.

Periodic Table of Videos , accessed December Podcasts Produced by The Naked Scientists. Download our free Periodic Table app for mobile phones and tablets. Explore all elements. D Dysprosium Dubnium Darmstadtium. E Europium Erbium Einsteinium. F Fluorine Francium Fermium Flerovium. G Gallium Germanium Gadolinium Gold. I Iron Indium Iodine Iridium. K Krypton. O Oxygen Osmium Oganesson. U Uranium. V Vanadium. X Xenon. Y Yttrium Ytterbium. Z Zinc Zirconium. Membership Become a member Connect with others Supporting individuals Supporting organisations Manage my membership.

Facebook Twitter LinkedIn Youtube. Discovery date. Identified as an element in , but known to the Greeks and Romans before 20BC. Discovered by. Andreas Marggraf. Origin of the name. The name is derived from the German, 'zinc', which may in turn be derived from the Persian word 'sing', meaning stone. Melting point. Boiling point. Zinc sulfate is used as a reagent in analytical chemistry and for paper bleaching, as a component of spinning bath in the manufacture of rayon, and as a chemical intermediary for the manufacture of carbamate fungicides, zinc metal, and other zinc compounds.

It is used in skin fresheners, glue, textile dyeing and printing, and preservatives for wood and hides. It is also used as a fireproofing agent, a fertiliser ingredient, a feed supplement, a herbicide, a miticide, as a soil treatment on lawns, and in sewage against animal pathogenic bacteria. Zinc sulfate can be used as a supplement for humans, animals and plants with zinc deficiency.

Zinc sulfide is used as a pigment for paints, oil cloths, linoleum, leather, and dental rubber, in white and opaque glass, plastics, dyeing, and in fungicides. It is used as a semiconductor, a photoconductor for solar cells, a pigment in paper, in infra-red thin film and transmitting devices, in detinning, and in optical filter coating. It is used as a phosphor in TV and X-ray screens, and in luminous dials of watches. Physical properties Zinc is easily obtained from its ores. Atomic Number: 30 Atomic Mass: It is slightly efflorescent and has a faint vinegar odour.

Zinc carbonate comes as colourless crystals, or a white, crystalline powder. Zinc chloride comes in the form of hygroscopic white granules, white crystals, fused pieces, or rods. It is odourless but its white fume has an acrid odour.

Its specific gravity is 2. Zinc chromate can be a yellow, fine powder or yellow prisms. It is odourless. Zinc cyanide is either a white powder, or colourless, rhombic crystals. It has the odour of bitter almonds. Zinc fluoride can exist as colourless crystals, needles, or a white crystalline mass. Its specific gravity is 4. Zinc oxide is a white solid which turns yellow on heating.

Zinc phosphide comes in the form of dark grey crystals, or a lustrous or dull powder. It has a faint phosphorus or garlic odour. Zinc potassium chromate is a yellow powder.

Zinc sulfate comes in the form of colourless rhombic crystals, transparent prisms or small needles. It is efflorescent in dry air. Chemical properties Zinc is insoluble in water but reacts readily with non-oxidising acids, forming zinc II and releasing hydrogen. Zinc acetate is soluble in water and alcohol. It crystallises from dilute acetic acid.

Zinc carbonate is soluble in dilute acids, alkalies and in ammonium salt solutions. It is insoluble in water, ammonia, pyridine, alcohol and acetone. Zinc chloride is very soluble in water, and quite soluble in alcohol and acetone. It is also soluble in hydrochloric acid, glycerol and ether. It is insoluble in ammonia. It is very deliquescent. Its fumes are corrosive to metals.

Zinc chromate is insoluble in cold water and acetone, and soluble in acid and ammonia. It is corrosive because of its oxidising potency. Zinc cyanide is insoluble in alcohol, and soluble in ammonium solutions, solutions of alkali cyanides and hydroxides. Zinc fluoride is soluble in water, and quite soluble in alcohol and acetone. It is also soluble in ammonium hydroxide, alkali, hydrochloric acid and nitric acid, slightly soluble in aqueous hydrofluoric acid, and insoluble in ammonia.

Zinc hydroxide can be precipitated from zinc solutions by addition of bases. It dissolves in aqueous sodium hydroxide and concentrated ammonia. Zinc oxide is formed when burning zinc metal in air or by pyrolysis of zinc carbonate or zinc nitrate. Zinc phosphide is practically insoluble in alcohol and water, and slightly soluble in benzene.

It is stable when dry. It reacts with acids and more slowly with water. Zinc sulfate is soluble in water, methanol and glycerol. It is insoluble in alcohol. Insoluble sulfates are formed when zinc sulfate is combined with lead, barium, strontium, and calcium salts.

Zinc sulfide is insoluble in water and alkalies, and soluble in dilute mineral acids. Australia's Zinc and compounds emission report. Description Zinc is an essential trace element in the diet of all living organisms from bacteria to humans. Entering the body Zinc can be inhaled or ingested. Exposure Zinc in trace quantities is essential for human health.

Workplace exposure standards Safe Work Australia sets the workplace exposure standards for particulate matter through the workplace exposure standards for airborne contaminants. The world's zinc production is still rising. This basically means that more and more zinc ends up in the environment. Water is polluted with zinc, due to the presence of large quantities of zinc in the wastewater of industrial plants. This wastewater is not purified satisfactory. One of the consequences is that rivers are depositing zinc-polluted sludge on their banks.

Zinc may also increase the acidity of waters. Some fish can accumulate zinc in their bodies, when they live in zinc-contaminated waterways. When zinc enters the bodies of these fish it is able to bio magnify up the food chain. Large quantities of zinc can be found in soils. When the soils of farmland are polluted with zinc, animals will absorb concentrations that are damaging to their health. Water-soluble zinc that is located in soils can contaminate groundwater. Zinc cannot only be a threat to cattle, but also to plant species.

Plants often have a zinc uptake that their systems cannot handle, due to the accumulation of zinc in soils. On zinc-rich soils only a limited number of plants has a chance of survival. That is why there is not much plant diversity near zinc-disposing factories. Due to the effects upon plants zinc is a serious threat to the productions of farmlands. Despite of this zinc-containing manures are still applied. Finally, zinc can interrupt the activity in soils, as it negatively influences the activity of microrganisms and earthworms.

The breakdown of organic matter may seriously slow down because of this. Read more on zinc in water.