Obtaining and using metals GapFill

The use of Earth's resources is becoming less sustainable. For example, copper ore is running out, so alternatives to mining it, including  phytoextractionfloraleachingphytoleachingfungiharvesting and bioleaching, are now being used.

Life cycle assessments can be used to judge the environmental impacts of products throughout their lifespan. They focus on several stages, starting from the extraction of raw materials, and ending with the product's  pricedisposalmanufacturingretail success. As a community, people can use resources more responsibly by reusing or  burningdisposing ofrecyclingreselling them.

When a metal reacts with oxygen,  a salta metal oxidea metal acida pure metal is formed. During this reaction, the metal is  oxidateddisplacedoxidisedalloyed because it has gained oxygen. Metals can react with non-metals to form  alloyssaltscatalystscarbonates. In these compounds, metals are positive ions, and more reactive metals will  chargereact withmagnetisedisplace less reactive metals. Many metals can be placed in an order of reactivity, called  a reactivity seriesa homologous seriesan oxidation columna reduction group, by observing their reactions with water or  carbon dioxidesilver nitratedilute acidnitrogen, because more reactive metals will react more vigorously.

Some metals, such as  goldironlithiummagnesium, are considered unreactive, and are found pure in nature. Other metals have to be  dugneutralisedpolymerisedextracted from their ores. This is usually done by  a reductiona deoxidationan extractiona precipitation reaction, where the metal loses oxygen. The metal oxide reacts with  a metal carbonatehydrogencarboncarbonic acid to form the pure metal and carbon dioxide.

Oxidation and reduction can also be defined another way. Oxidation is the loss, and reduction is the gain, of  nitrogenoxygencarbonateelectrons. These reactions can be represented using  chargeelectroionichalf-equations.