9 Metals Flashcards
Uses of aluminium
Manufacture of aircraft: low density
Manufacture of overhead
electrical cables: low density
and good electrical conductivity
Food containers: resistance to corrosion
Uses of copper
electrical wiring because of its good electrical conductivity and ductility
alloy
mixture of a metal with other elements
Brass
Alloy - mixture of copper and zinc
Stainless stell
Alloy - mixture of iron and elements such as chromium, nickel and carbon
Why are alloys sometimes more useful than pure metals?
Alloys can be harder and stronger than the pure metals
Use of stainless steel
Cutlery: hardness and resistance to rusting
Why are alloys harder and stronger than pure metals?
the different sized atoms in alloys mean the layers can no longer slide over each other as easily.
Order of reactivity series
Potassium
Sodium
Calcium
Magnesium
Aluminium
Carbon
ZInc
Iron
Lead
Hydrogen
Copper
Silver
Gold
Potassium reaction with cold water
Potassium + water –> potassium hydroxide + hydrogen
2K + 2H2O → 2KOH + H2
Sodium reaction with cold water
Sodium + water –> sodium hydroxide and hydrogen
2Na + 2H2O → 2NaOH + H2
Calcium reaction with cold water
Calcium + water –> calcium hydroxide + hydrogen
Ca + 2H2O –> Ca(OH)2 + H2
Alkali metal + water –>
alkali metal hydroxide + hydrogen
Metal + steam –>
Metal oxide + hydrogen
magnesium reaction with steam
Magnesium + steam –> magnesium oxide + hydrogen