Metals Flashcards
What do metals form?
a giant metallic lattice
What is a metallic lattice?
electrostatic attraction between positive metal ions and delocalised electrons
What are the properties of metals?
good conductors of electricity and heat
high mp/bp
malleable
sonorous
shiny
high density
ductile -> can be made into wires
Why are metals strong?
due to strong electrostatic between positive metal ions and delocalised electrons which is strong
Why do metals have a high melting point?
due to strong electrostatic between positive metal ions and delocalised electrons require lots of energy to overcome
higher charge = higher mp
Why do metals conduct when solid and molten?
delocalised electron are free to move
Why are metals malleable?
rows of ions can slide over each other and delocalised electrons can move to hold the structure together
What are group 1 called?
alkali metals
What are the physical properties of group 1?
high melting point
grey
shiny
hard
good thermal and electrical conductor
How are metals stored?
In oil to stop it reacting with oxygen and water
Explain the trend in reactivity down group 1
- All group 1 need to lose 1 electron
- down the group = more shells
- outer electrons further away from
- nucleus therefore weaker
attraction - easier to remove the electron
Physical observations of lithium
low density
dark grey
soft metal
Physical observations of sodium
high density
lighter grey
softer
Physical observations of potassium
very soft
lighter grey
Physical observations of rubidium
lighter grey than K
softer than k
Physical observations of caesium
lighter grey than rubidium
softer than rubidium
Observations of lithium with oxygen
shiny surface dulls quickly
Observations of sodium with oxygen
shiny surface dulls quicker than lithium
Observations of potassium with oxygen
shiny surface disappears quicker Na
Observations of rubidium with oxygen
shiny surface disappears quicker than k
Observations of caesium with oxygen
shiny surface disappears quicker than rubidium
Observations of lithium with water
moves around, fizzing, metal disappears, gas given off, alkali produced as UI turns blue/purple
Observations of sodium with water
moves around more than lithium, fizzing, turns into sphere than disappears, more gas given off
Observations of potassium with water
fizzes very quickly, caught fire, more gas given off, flame is lilac, pop given off - hydrogen react with O₂
Observations of rubidium with water
ignites as soon as hits water, more gas given off, hydrogen reacts - flames given off
lithium + water -> ?
hydrogen + lithium hydroxide
lithium disappears
hydrogen causes bubbles
Formula for carbonate ions?
CO₃⁻²
What is decomposition?
breaking something down
What is thermal decomposition?
breaking something down using heat
What is the formula for thermal decomposition of metal carbonates?
metal carbonate -> metal oxide + carbon dioxide
What is the test for carbon dioxide?
bubble through limewater
turns cloudy
What colour is copper carbonate?
green
What colour is copper oxide?
black
formula for thermal decomposition of copper carbonate?
copper carbonate -> copper oxide + carbon dioxide
Describe Mg(s)
solid, shiny, silver
Describe Fe(s)
grey, solid, dull
Describe Cu(s)
solid, brown, shiny
Describe MgSO₄
aqueous
Describe FeSO₄(aq)
green clear solution
Describe CuSO₄(aq)
blue clear solution
MgSO₄ reacting with Fe and Cu?
no reaction
FeSO₄ reacting with Mg and Cu?
Mg = gas, Mg moved, grey solid produced
Cu = no reaction
CuSO₄ reacting with Mg and Fe?
Mg = gas, black solid produced
Fe = iron turned black
Why is Mg most reactive out of Mg, Fe, Cu?
Mg reacted with everything other than itself
Why is Cu least reactive out of Mg, Fe, Cu?
Cu reacted with nothing
What is the reactivity series?
Please Stop Literally Calling Me A Careless Zebra, Can Instead Now Try Learning How Copper Maybe Saves Gold
Potassium, Sodium, Lithium, Calcium, Magnesium, Aluminium,
Carbon,
Zinc, Chromium, Iron, Nickel, Tin, Lead,
Hydrogen,
Copper,Mercury, Silver, Gold
What is a spectator ion?
plays no part in chemistry
What is a redox reaction?
Both reduction and oxidation has occurred
What is an oxidising agent?
Helps something to be oxidised
What is a reducing agent?
Helps something to be reduced
Where do metals come from?
the ground
What is an ore?
Rock containing a metal compound
How do we extract the most reactive metals?
(K, Na, Li, Ca, Mg, Al)
electrolysis = breaking down a compound using electricity
How do we extract the middle metals?
(Zn, Cr, Fe, Ni, Sn, Pb, Cu)
Displacement using carbon
carbon is more reactive, cheap + easily available
How do we extract Mercury and Silver?
don’t require extraction, but may need purifying
How do we extract native metals
(Gold, platinum)
not found as ores
require no extraction
Practical: Extracting iron
Describe
Add iron(III) oxide and carbon to crucible
Weigh
Heat strongly (no lid, 5 mins)
Reweigh after cool
Use splint and magnet to find iron produced
Practical: Extracting iron
Why did mass decrease?
one of the products (CO₂) is a gas therefore can escape
What is rust?
Hydrated iron(III) oxide
Explain the first stage of rusting
Oxidation of Iron
4Fe + 3O₂ -> 2Fe₂O₃
Explain the second stage of rusting
hydration of iron (III) oxide
Fe₂O₃ + XH₂O -> Fe₂O₃ * XH₂O
X: amount of water varies
Rusting is a chemical process by which…
Iron is oxidised and hydrated
What two substances does rusting require to occur?
water and oxygen
What are the three methods to prevent rusting?
Barrier, Sacrificial protection, Galvanising
What is the barrier method?
Coating Fe in plastic, oil, or paint
+ easy
- has to be replaced
What is sacrificial protection?
add a block of more reactive metal
iron displaced as soon as any rust forms
+ easy method, very effective
- Mg needs to be replaced therefore expensive
What is galvanising?
Specifically coating Fe in Zinc
Prevents O₂/H₂O reacting with iron
Zinc can act as sacrificial metal if crack occurs
e.g. iron bucket
nails
ships
What are alloys?
mixtures of metals with one or more other elements - usually other metals or carbon
What are the commonly known alloys?
Steel: iron + carbon
Brass: copper + zinc
Bronze: copper + tin
Why are alloys harder / less malleable?
Presence of another metal makes it harder for rows to slide
Why are different metals and alloys used for different purposes?
Material must be suited to its use
What is iron used for? Why?
making steel
steel is more useful than iron
What is low-carbon steel used for? Why?
ships, cars, bridges
strong, still malleable
What is stainless steel used for? Why?
cutlery + cooking utensils
high mp & strong
shiny & prevent corrosion
What is copper used for? Why?
electrical wiring, water pipes, cooking pots
excellent conductors of electricity, unreactive to oxygen + water
flexible
What is Aluminium used for? Why?
foil, aircraft bodies, drinks cans
malleable, light, fairly unreactive
