CBSE CLASS-10 CHEMISTRY Chapter-3 Metals and Non-metals
CHAPTER - 3
Metals And Non-metals
Till now we have about 115 elements on the basis of physical and chemical property. It can be classified into three category.
( i ) Metals
( ii ) Non-Metals
( iii ) Metalloids
1. Metals
Element having most of metalic property are know as metals.
Physical Property
( i ) All metal generally poses special shine called metallic lustres.
( ii ) Metal are generally melleable and ductile.
( iii ) Metal are generally good conducter of electricity except lead( pb ).
( iv ) Metal are generaly soneras.
( v ) Metal have high melting boiling point.
( vi ) The mecanical strength of metal are high.
( vii ) Metal are generally hard except sodium & potassium.
( viii ) Metal are generally solid at room temperature except,Mercury,Gallium,Cesium.
( ix ) The density of metal are generally high.
( x ) Metals are generally silveris grey in color except gold and copper.
2. Non-Metal
Element which do not have metalic property is known as non-metal.
Physical Property
( i ) Generally Non-metal are not lustres.
( ii ) Non-Metals are brittle in nature.
( iii ) Non-Metal are generally bad conducture of heat and electricity.
( iv ) Non-Metal are not sonorous.
( v ) Non-Metal have less boiling and melting point.
( vi ) It's mechanical is very weak.
( vii ) It is generally solid liquid and gas at room temp.
The density of non-metalic is very less
Chemical Properties of Metal
( i ) Reaction with Oxygen ( O2 )
Metal forms metallic oxide on reacting with oxygen.
Ex - Metal + Oxygen ------> Melallic Oxide
4Na + O2 -------> 2Na2O
2Mg + O2 -------> 2Mg2O
4K + O2 ---------> 2K2O
4Al + 3O2 ---------> 2Al2O3
2Ca + O2 --------> 2CaO
The oxide of metal are basic in nature means that the aqus solution of metallic oxide behaves like a base.
Na2O + H2O --------> 2NaOH
MgO + H2O --------> Mg(OH)2
K2O + H2O --------> 2KOH
Al2O3 + H2O --------> Al(OH)3
CaO + H2O --------> Ca(OH)2
Oxide of some metal are Amphoteric in nature such oxide shows both acidic and basic characture.
Ex- Aluminium Oxide, Zink Oxide
Base + Acid ------> Salt
Al2O3 + 2AlCl3 + 3H2O
Al2O3 + 2NaOH --------> 2NaAlO2(Sodium aluminate) + H2O
2. Reaction with water
Metal forms metalic hydroxide and librate hydrogen gas on reaction with water.
Ex - Metal + Water -------->Metallic hydroxide + H2
Different metal react differently with water. Some react with cold water some react with hot water where some react with hot water whereas some do not react with water.
Sodium react with water it forms sodium hydroxide and hydrogen.
2Na + 2H2O -------> 2NaOH + H2
2K + 2H2O -------> 2KOH + H2
Mg + H2O -------->Mg(OH)2 + H2
Metals such as gold, Silver, Copper do not react with water.
3. Reaction with stream
Metal forms metallic oxide on reacting with steam.
Metal + Steam -------> Metallic
what are Ampoteric oxide ? How zink oxide shows its Ampoteric nature ?
An Amphoteric compound is a molecule or ion that can react both as an acid as well as base. Many metal such as copper, zink, Tin, Lead, Aluminium and beryllium,forms amphoteric oxide or hydroxide it depends on the oxidation state of the oxide.
What happen when Red hot Iron react with steam ?
Iron does not react with water in the ordinary temperature. It react only with stream.When steam is passed over red hot iron, Iron ( ii,iii ) oxide and hydrogen gas are formed.
3Fe + 4H2O 
Fe3O4 + 4H2
4. Reaction with Acids
Metal from metallic salt and librate hydrogen gas on reacting with acid.
Ex- Metal + Acid -------> Metallic Salt + H2
2Na + 2HCl --------> 2NaCl + H2
Ca + H2SO4 ------> CaSO4 + H2
2Al + 3H2SO4 ------> Al(SO4)3 + 3H2
Ca + CH3CooH --------> (CH3Coo)2Ca (Calcium Acitate) + H2
When metal is allowed to react with nitric acid then hydrogen gas not evolved it is because the oxidiging nature of nitric acid as soon as hydrogen gas is formed it get oxidiged into water.
Magnesium & Magnise metals when react with very dillute nitric acid then salt as well as hydrogen gas is formed.
Aquaragia
It is homoginus solution of nitric acid and hydrocloric acid mixed together in the ratio 1:3. It is highly corrosive in nature it can dissolve almost all metal even gold and platinium also.
HNO3 : HCl
1 : 3
Reactivity Series
When more reactive metal react with the salt of less reactive metal then more reactive metal displace the less reactive metal and forms its own salt.
Ex :
CuSO4 + Zn --------> ZnSO4 + Cu⬇
AgNO3 + Mg ---------> 2MgNO3 + 2Ag⬇
CuSO4 + Fe -----------> FeSO4 + Cu ⬇
Reaction with Clorine
Metals form ionic cloride on reacting with clorine.
Na + Cl2 ---------> 2NaCl ( Sodium cloride )
Mg + Cl2 ----------> 2MgCl2
Reaction with hydrogen
Metals form metalic hydried on reacting with hydrogen.
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