METALS
Physical properties
-malleable
-ductile
-conductor of elec
-conductor of heat
-high m.p. and b.p. (except Group I & mercury)
-shiny

alloys- change properties by adding other elements; > -harder, -diff m.p., -oxidise (rust) less

most reactive > stable as ions > K > Na > Ca > Mg > Al > Zn > Fe > Sn > H > Cu > Ag > Au > stable as metals > least reactive

Reaction w/ water
Very reactive metals(K-Ca) (soluble oxides); react w/ cold water > metal hydroxide + H₂ gas
v.reactive metals: METAL + WATER -> METAL HYDROXIDE + HYDROGEN GAS
Reactive metals (Mg-Fe); react w/ steam to make metal oxide + hydrogen gas
reactive metals: METAL + WATER -> METAL OXIDE + HYDROGEN GAS
Non-reactive metals (Sn-Au); don't react w/ water or steam (at normal temp), metals below H never react w/ water

Reaction w/ dilute acids
METAL + ACID -> SALT + HYDROGEN GAS
Very reactive metals(K-Na); react quickly (explosively) w/ acid > salt + hydrogen gas
Reactive metals(Ca-Sn); react much slower w/ acid > salt + hydrogen gas
Calcium stops reacting w/ H₂SO₄ as insoluble layer of white CaSO₄ forms over Ca which is impermeable to & doesn't react w/ acid
Non-reactive metals(below H); don't react w/ acids

Reduction of metal oxides
METAL OXIDE + HYDROGEN GAS -> METAL + WATER
METAL OXIDE + CARBON -> METAL + CARBON DIOXIDE
METAL OXIDE + METAL -> METAL + METAL OXIDE (more reactive metals > metal oxide)

Metal displacement; METAL + METAL ION -> METAL ION + METAL (more reactive metal > ions)

Metal carbonates: most decompose on heating > metal oxide + CO₂, Na + K don't decompose, Ag + Au carbonate don't exists

Extraction and uses of metal
Very reactive (K-Al); stable as ions > difficult to reduce > need to electrolyses molten ores
Reactive (Zn-Ag); extracted from ores by heating w/ carbon



C + O₂ -> CO₂ + HEAT
CO₂ + C -> 2CO
Fe₂O₃ + 3CO -> 2Fe + 3CO₂
CaCO₃ -> CO₂ + CaO
CaO + SiO₂ -> CaSiO₃ (slag, for roads)

Coke(~pure C)- make CO₍₂₎ and heat [coal (mixture)>heat (no air) >coke]
Hot air(O₂)- make heat & carbon dioxide
Haematite- iron ore (source)
Limestone(CaCO₃)- produces CO₂(>CO) & CaO (> slag)

Impurities(SiO₂, P and S oxide) removed by reaction w/ CaO > slag

Iron from a blast furnace is impure & brittle (due to C), to purify: use O₂ and lime (CaO)
Mild steel: Mn, Si, C added: used for vehicles, ships, steel rods (reinforce concrete): very strong & cheap compared to other alloys
Stainless steel: Cr, Ni, C added: used in chemical industries, for medical instruments, for cutlery, in plumbing: strong & doesn't rust

Aluminium (extracted by electrolysis)
-low density, strong, conductor of electricity, resistant to corrosion
-Al exposed to air > Al₃O₂ layer forms (impermeable to O₂) > rusting stops [Fe₂O₃ permeable > rusting continues]
-in large electrical wires/ cables- good conductor of elec and is light (cable has steel core- strong)
-for aircraft bodies and wings from Al alloy- light and impurities can make it strong
-for food containers; cans and trays- light, resistant to corrosion

Zinc; galvanise iron (dipping Fe in molten Zn > thin layer of Zn > impermeable oxide layer > protects iron, forms brass (+copper)

Copper; electrical wires- good conductor of elec, forms bronze (+Sn) / brass (+Zn)

Organic Chemistry
Non-metals
The Particulature Natrue of Matter
Experimental Techniques
Atoms, Elements and Compounds
Stoichiometry + Mole Concept
Acids + Bases
Chemical Reactions + Electrolysis
Rate and Heat of Reactions + Reversible Reactions
The Periodic Table

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