Metals Review

PHYSICAL PROPERTIES

High melting points
Solid at room temperature except Hg
Good conductors of electricity and heat
Malleable and Ductile
Shiny surface
High density

Chemical Properties of Metals

When metals react they ionise by losing electrons to fprm cations (+). The metal behaves as a reducing agent because it gives electrons to the other reactant (it causes the other reactant to gain electrons). This forms IONIC COMPOUNDS.

Reactions of metals with dilute acids

Metal + acid = Salt + hydrogen

eg. 2Na(s) + 2HCl(aq) = 2NaCl(aq) + H2(g)

Reactions of metals with oxygen

Metal + Oxygen = metal oxide

eg. 4K(s) + O2(g) = 2K2O(s)

2Cu(s) + O2(g) = 2CuO(s)

Reactions of metals with water

metal + water = metal hydroxide + hydrogen

eg. Ca(s) + 2H2O(l) = Ca(OH)2 (aq) + H2 (g)

metal + steam = metal oxide + hydrogen

3Fe + 4H2O = Fe3O4(s) + 4H2(g)

REACTIONS OF METALS WITH DILUTE ACIDS, OXYGEN AND WATER

Metal	Description of the reaction with dilute acids	Description of the reaction when the metal is heated in air	Description of reaction with water
Potassium	Reacts extremely violently	Burns vigourously with lilac flame	Reacts vigourously with cold water
Sodium	Reacts violently	Burns vigourously with orange flame	Reacts vigourously with cold water
Calcium	Reacts fairly violently	Burns easily with a brick red flame	Reacts moderately with cold water
Magnesium	Reacts very vigorously	Burns easily with a bright white flame	Reacts very slowly with cold and hot water Reacts vigourously with steam
Aluminum	Reacts vigourously	Burn when heated strongly especially when powdered	Do nnot react with hot or cold water React with steam
Zinc	Reacts fairly vigourously
Iron	Reacts very slowly
Copper	Do not react with dilute acids	Does not burn when heated but forms and oxide coating if heated very strongly	Do not react with water or steam
Silver		Does not react, even when heated very strongly.

REACTIONS OF METAL COMPOUNDS WITH DILUTE ACIDS

metal oxide + acid = salt + water

ZnO(s) + 2HCl(aq) = ZnCl2(aq) + H2O(l)

metal hydroxide + acid = salt + water

Mg(OH)2 (s) + H2SO (aq) = MgSO4(aq) + 2H2O(l)

metal carbonates + acid = salt + carbon dioxide + water

CuCO3(s) + 2HNO3(aq) = Cu(NO3)2 (aq) + CO2(g) + H2O(l)

DECOMPOSITION OF METAL COMPOUNDS WHEN HEATED

Metal	Metal	Compounds
	Hydroxides	Carbonates	Nitrates
Potassium Sodium	The hydroxides are stable they do not decompose	Carbonates are stable they do not decompose	Decompose slightly to form the metal nitrate and oxygen eg. 2NaNo3(s) = 2NaNO2(s) + O2(g)
Calcium Magnesium Aluminum Zinc Iron Lead Copper	Decompose to form the metal oxide and water (as steam) eg. Ca(OH)2 (s) +
Silver