The extraction of metals

Descripción

Mapa Mental sobre The extraction of metals, creado por jasmin.sahota el 31/05/2013.
jasmin.sahota
Mapa Mental por jasmin.sahota, actualizado hace más de 1 año
jasmin.sahota
Creado por jasmin.sahota hace alrededor de 11 años
65
1

Resumen del Recurso

The extraction of metals
  1. found in ores containing oxygen and sulfur
    1. iron oxide, Fe2O3
      1. Fe3+ to Fe
        1. reduction from a 3+ to 0
      2. copper sulphide CuS, to copper
        1. +2 to O
        2. need a cheap, readily available reducing agent
          1. impurities (gangue) clay and rock have to be removed
            1. non-polluting and easy to dispose of by-products
          2. converting sulphides to oxides
            1. heating in air, called roasting
              1. zinc sulphide converted to zinc oxide
                1. ZnS(s) + 1.5O2(g) ---> ZnO(s) + SO2(g)
                  1. however SO2 is an acidic gas and produces (sulphuric acid) when mixed with water, a contributor to acid rain
                    1. however SO2 can be coverted to sulkphuric acid in controlled conditions and sold for a variety of purposes
                      1. SO2(g)+H2O(g)+0.5O2(g)-->H2SO4(l)
            2. choosing a reducing agent
              1. Coke
                1. impure form of carbon
                  1. cheaply obtained by heating coal in the absence of air
                    1. however so metals require very high temperatures (ends up uneconomic)
                      1. at high temps metal react with carbon to form carbides
                2. Hydrogen
                  1. made from methane and water
                    1. used to extract tungsten
                  2. metals high up on the reactivity series
                    1. can use electrolysis
                      1. such as sodium and aluminium
                    2. use a more reactive metals
                    3. recycling and the environment
                      1. iron
                        1. can be melted down and reformed
                          1. easily separated from other materials because it is magnetic
                            1. does not produce CO2 when melted down
                              1. whereas extraction does
                                1. however energy needs to melt involves the production of CO2
                        2. aluminium
                          1. also recycled by melting
                            1. only uses 5% of energy needs for extraction
                              1. recycling avoids large amount of CO2 formed
                                1. however big rising costs in sorting and transporting of recycled material
                        Mostrar resumen completo Ocultar resumen completo

                        Similar

                        Inglés - Verbos Compuestos I (Phrasal Verbs)
                        maya velasquez
                        Universidades de Latinoamérica
                        Diego Santos
                        Vocabulario Inglés (I y II) para la Selectividad
                        maya velasquez
                        REVOLUCIÓN RUSA (1917)
                        coorprogresistal
                        MAPAS CONCEPTUALES DIGITALES
                        carolinaordonezm
                        CAMPOS DE ACCIÓN DE LA INGENIERÍA INFORMÁTICA
                        Jorge Mora
                        CAMBIO CLIMATICO
                        sharon esteban
                        Properties of musical tones
                        Olga Veiga
                        Sistema Cardiovascular
                        Kevin BD
                        Elementos de la COMUNICACIÓN
                        belladetormes
                        Texto Narrativo
                        Diana Banda