C9 - metals Flashcards
define delocalized
free to move
define metallic bonding
positive metal ions in a sea of delocalised electrons held by electrostatic forces
which bonds have giant lattice structure
-metallic bonds
-ionic bonds
-giant covalent bonds
why can metals conduct electricity
-delocalised electrons are free to move and carry charge freely through the structure
properties of metal
-malleable
-high melting/ boiling point except mercury
-good thermal conductivity
-good electrical conductivity
-ductile
which metal has a low boiling point
mercury
define malleable
bent or hammered into shape
define ductile
drawn into wires
why are metals malleable/ ductile
-particles are in ordered structure
-layer can slide over each other
define good thermal/ electrical conductivity
-can conduct heat/ electricity well
why do metals have good thermal/ electrical conductivity
-delocalised electrons can more freely & carry energy/ charge through the structure
-Only energy can be passed by vibrating particles too
define alloy
A mixture of a metal with another substance
why an alloy is more useful than the pure metal
-it’s harder
-because other element disrupts the lattice structure &
-makes it more difficult to remove the layers form the metal
define brass
An alloy of copper and zin
define steel
alloy that contains iron and other substances
Why is nickel and chromium alloyed with iron
Chromium prevents rusting
nickel makes it harder
uses of aluminum
-manufacture of aircraft - low density
-manufacture of overhead cables - low density, good electrical conductivity
-food containers - resistant to corrosion
uses of copper
-in electrical wiring - good electrical conductivity
uses of mild steel and stainless steel
-mild steel for car bodies & machinery
-stainless steel for chemical plants and cutlery
reactivity series
-Please Stop Calling Me A Cute Zebra, I Like Hot Corn Soup Generally
-Potassium K
-Sodium Na
-Calcium Ca
-Magnesium Mg
-Aluminum Al
-Carbon C
-Zinc Zn
-Iron Fe
-Lead Pb
-Hydrogen H
-Copper Cu
-Silver Ag
-Gold Au
(K over Na because it has more periods)
How does the reactivity of a metal relate to how easy it is to extract from its ore
-more reactive the metal, more difficult to extract the metal form its ore
How does the reactivity of a metal relate to its tendency to form a positive ion
-more reactive the metal, easier to lose valance electrons and form positive ions
how does reactivity series reactive with acid (H+)
-K, Na, Ca = produce H2 + vigorous
-Mg to Fe = less reactive as go down
-Cu, Ag & Au = don’t react
how does reactivity series reactive with O2
-K & Na = burns brightly + vigorous
-Ca & Mg= forms oxide + burns brightly
-Al to Cu = less reactive as go down
-Ag & Au = don’t react
how does reactivity series reactive with water (solid & liquid)
-K, Na, Ca = react liquid water
-Mg to Fe = react with steam, less reactive as go down
-H to Au = don’t react
formula for G1/2 metal + cold water
-> _________hydroxide + H2
formula for G1/2 metal + steam
-> _________oxide + H2
How are elements above carbon in the reactivity series extracted from their ores
Electrolysis
How are elements below carbon in the reactivity series extracted from their ores
using carbon
which elements don’t need to be extracted & why
-Platinum & Silver
-they’re pure metals
How is iron extracted from the metal ore hematite in the blast furnace
By heating with carbon
word equation for rusting
Iron 3 + water + oxygen -> hydrated iron 3 oxide
factors that increase rusting
-more acid rain, more rust
-more salt, more rust
-need water + O2
ways to prevent rusting
-painting eg. car bodies
-oiling eg bicycle chains
-coated with a layer of plastic
-greasing eg nuts & bolts
define galvanizing
coating iron/ steel in a layer of zinc
define ore
A rock that contains a high enough percentage of metal for economic extraction
how does galvanizing work
-zinc is more reactive & reacts with O2 before iron (sacrificial protection)
-zinc stops O2 from reaching iron underneath
define hematite
-ore containing iron oxide
-Fe2O3
3 symbol equations with states for process of extracting iron from hematite
-C (s) + O₂ (g) → CO₂ (g)
-C (s)+ CO₂ (g)→ 2CO (g)
-Fe₂O₃ (s) + 3CO (g) → 2Fe (L) + 3CO₂ (g)
why limestone (CaCO₃) is used in the blast furnace
To remove acidic impurities such as silicon (IV) oxide
2 symbol equations for process of removing impurities
-CaCO₃ → CaO + CO₂ (thermal decomposition)
-CaO + SiO₂ → CaSiO₃ (slag)
what is coke
carbon
