chapter 15-the reactivity series

• the melting point of metals increases with increasing atomic number due to stronger metallic bonds, which require more energy to break.
• in the reactivity series, metals are arranged from the most to least reactive
• metal oxides can be reduced by carbon or hydrogen gas
• metals above hydrogen in reactivity react with hydrochloric acid to produce hydrogen gas
• rusting only occurs in the presence of oxygen and water
• prevention of corrosion methods, sacrificial protection and barrier method
• metal oxide + carbon -- heat --> metal + carbon dioxide
• some reaction can only take place with steam and not water because steam has more energy compared to water, and thus meets activation energy more easily
• metal displacement occurs when a more reactive metal takes the place of a less reactive metal in its aqueous oxide or solution
• lead is reduced by hydrogen because its reactivity is almost equal
• system = reactants + products
• a more reactive metal has a higher tendency to form a positive ion compared to a less reactive metal
• lead(II) oxide + hydrogen = lead + steam
• metal displacement reactions are redox reactions as the more reactive metal is oxidized due to losing electrons
• more reactive metals form ions more easily while less reactive metals like to stay as atoms
• metals reactivity goes down as they move down the group as electrostatic forces of attraction decreases as valence electrons are further away from the nucleus. Thus it is easier to lose electrons
• the more reactive a metal is, the harder its carbonate is to decompose through heat
• the more reactive a metal is, the more stable its carbonate is due to stronger bonds
• metal extraction methods- reduction by carbon and electrolysis
• rust is very brittle and flaky