C7 Metals Flashcards
what is METALLIC BONDING?
lattice of cations
in a sea of delocalized electrons
properties of METALS?
good conductor of heat and electricity
high m/b point
malleable and ductile
why do metals conduct heat and electricity?
delocalized electrons
why do metals have high m/b points?
strong force of attraction between metal ions and delocalized electrons
→ more energy needed to break the bonds
why are metals malleable and ductile?
LAYERS OF ION in lattice structure SLIDE PAST one another due to delocalized electrons
properties of TRANSITION METALS?
high density
high melting point
form colored compounds
why do transition metals have high melting points?
each atom is bonded to electrons
each ion is bonded to other ions
→ more energy to break the bonds
what are transition metals often used as?
catalysts
e.g. Fe in haber process to make NH3
what are ALLOYS?
mixtures of metals
why do alloys have different properties from the metals they contain?
what are the different properties?
- difference atoms distort regular lattice structure
- harder for layers to slide past one another
→ stronger, less flexible
properties and uses of ALUMINUM?
resistant to corrosion + strong + light → aircraft
conduct heat + non-toxic → saucepan
properties and uses of ZINC?
cheap, reactive → coating iron (galvinizing)
properties and uses of COPPER?
conduct electricity → electrical wires
properties and uses of BRONZE?
doesn’t corrode → medals
properties and uses of BRASS?
doesn’t corrode → music instruments
composition, properties and uses of STEEL?
Fe+C
very hard → cutting tool
properties and uses of MILD STEEL
easily shaped → car body
properties and uses of DURIRON?
not affected by acid → pipes in chemical factories
properties and uses of STAINLESS STEEL?
doesn’t rust → car parts, cutlery
what is REDOX reaction?
loss/gain of electrons (oxidation, reduction)
an element is oxidized when it
… electrons?
loses electrons
OIL - Oxidation Is Loss of electrons
an element is reduced when it
… electrons?
gains electrons
RIG - Reduction Is Gain of electrons
what can more reactive metals do to less reactive metals?
DISPLACE them from their salt solution
write the
1. SYMBOL EQUATION
2. HALF EQUATION
for copper reacting w/ silver nitrate
Cu (s) + 2AgNO3 (aq) → Cu(NO3)2 (aq) + 2Ag (s)
Cu(s) → Cu2+ (aq) + 2eˉ
Ag+ (aq)+ 1eˉ →Ag(s)
in REDOX rxn, more reactive metals are …?
oxidized // reducing agent
in REDOX rxn, less reactive metals are …?
reduced // oxidizig agent
the reactivity series?
Potassium Sodium Calcium Magnesium Aluminum (Carbon) Zinc Iron Tin Lead (Hydrogen) Copper Silver Gold
metals more reactive than what element can react with cold water+steam+acid?
calcium
metals more reactive than what element can react with steam+acid but not cold water?
hydrogen
how are the most reactive metals extracted? what is the disadvantage of it?
electrolysis
expensive and takes up lots of energy
how are metals less reactive than carbon extracted?
heat their oxides with carbon → REDUCED by carbon
how are the least reactive metals extracted?
they are found as pure elements
mixtures from which metals can be extracted are called?
ores
why do ores need to be recycled?
what are good+bad sides of recycling?
they are finite resources
- less landfill
- expensive
how is iron extracted?
blast furnace
describe the process of IRON EXTRACTION in BLAST FURNACE
equations
iron extraction:
- C + O2 → CO2
- C + CO2 → CO
- CO + Fe2O3 → Fe (l) + CO2
slag removal:
- CaCO3 → CaO + CO2
- CaO + SiO2 → CaSiO3 (l)
what are the materials needed for iron extraction in blast furnace?
iron ore - Fe2O3
limestone - CaCO3
coke - C
BLAST FURNACE:
what happens to the SLAG?
REMOVED → make CEMENT
BLAST FURNACE:
what happens to the MOLTEN IRON?
SINK to bottom (dense) → tapped off → turned into steel
what is zinc’s ore called?
zinc blende (ZnS)
what is iron’s ore called?
hematite (Fe2O3)
what are the conditions for rusting?
water
oxygen
what happens to the rate of rusting if there’s impurity in water?
faster
why does iron need to be protected from rusting?
rust weakens its structure and strengths
what is physical protection of rust? what are the drawbacks?
keeping air and oxygen away from surface:
- cover with oil, plastic, paint (easy to rub/peel off)
- cover with less reactive metal (loses protection and rusts faster once coating is scratched)
what is sacrificial/galvanizing protection of rust? give an example
cover with more reactive metal → reactive metal reacts with oxygen first → leaves iron unreacted
e.g. zinc
why does aluminum not corrode?
aluminum oxide layer → prevents metal from contact with oxygen/air
