Chapter 18: Metals
Metals are found in group 1, group II and the Transition Block of the periodic table.
As we go down the group there is an increase in metallic character.
Metals react with cold water and form a metal hydroxide and hydrogen gas
metal + water β metal hydroxide + hydrogen
For example calcium: Ca (s) + 2H2O (l) β Ca(OH)2 (aq) + H2 (g)
metal + acid β salt + hydrogen
Fe (s) + 2HCl (aq) β FeCl2 (aq) + H2 (g)
metal + oxygen β metal oxide
2Cu (s) + O2 (g) β 2CuO (s)
Example> COPPER (II) OXIDE
Magnesium is above copper in the reactivity series,
magnesium is more reactive so can displace copper from its oxide
Copper is reduced
The reducing agent in the reaction is magnesium: copper oxide + magnesium β copper + magnesium oxide
CuO (s) + Mg (s) β Cu (s) + MgO (s)
Displacement reactions between metals and aqueous solutions of metal salts
Any metal will displace another metal that is below it in the reactivity series from a solution of one of its salts
Magnesium + copper sulfate
Magnesium is a reactive metal and can displace copper from a copper sulfate solution
, more reactive metal slowly disappears from the solution, displacing the less reactive metal.
Thermal decomposition reactions: Some compounds decompose or breakdown when they are heated to sufficiently high temperatures
These reactions are called thermal decomposition reactions.
metal hydroxide β metal oxide + water
Zn(OH)2 (s) β ZnO (s) + H2O (l)
metal carbonate β metal oxide + carbon dioxide
MgCO3 (s) β MgO (s) + CO2 (g)
metal nitrate β metal nitrite + oxygen
2NaNO3 (s) β 2NaNO2 (s) + O2 (g)
metal nitrate β metal oxide + nitrogen dioxide + oxygen
2Cu(NO3)2 (s) β 2CuO (s) + 4NO2 (g) + O2 (g)
Metals are found in group 1, group II and the Transition Block of the periodic table.
As we go down the group there is an increase in metallic character.
Metals react with cold water and form a metal hydroxide and hydrogen gas
metal + water β metal hydroxide + hydrogen
For example calcium: Ca (s) + 2H2O (l) β Ca(OH)2 (aq) + H2 (g)
metal + acid β salt + hydrogen
Fe (s) + 2HCl (aq) β FeCl2 (aq) + H2 (g)
metal + oxygen β metal oxide
2Cu (s) + O2 (g) β 2CuO (s)
Example> COPPER (II) OXIDE
Magnesium is above copper in the reactivity series,
magnesium is more reactive so can displace copper from its oxide
Copper is reduced
The reducing agent in the reaction is magnesium: copper oxide + magnesium β copper + magnesium oxide
CuO (s) + Mg (s) β Cu (s) + MgO (s)
Displacement reactions between metals and aqueous solutions of metal salts
Any metal will displace another metal that is below it in the reactivity series from a solution of one of its salts
Magnesium + copper sulfate
Magnesium is a reactive metal and can displace copper from a copper sulfate solution
, more reactive metal slowly disappears from the solution, displacing the less reactive metal.
Thermal decomposition reactions: Some compounds decompose or breakdown when they are heated to sufficiently high temperatures
These reactions are called thermal decomposition reactions.
metal hydroxide β metal oxide + water
Zn(OH)2 (s) β ZnO (s) + H2O (l)
metal carbonate β metal oxide + carbon dioxide
MgCO3 (s) β MgO (s) + CO2 (g)
metal nitrate β metal nitrite + oxygen
2NaNO3 (s) β 2NaNO2 (s) + O2 (g)
metal nitrate β metal oxide + nitrogen dioxide + oxygen
2Cu(NO3)2 (s) β 2CuO (s) + 4NO2 (g) + O2 (g)