Characteristics of Alkali Metals:



1.    Each member of group IA or group 1 has ns1 arrangement of electrons where n represents for the outermost shell i.e., all these members possess only on electron in their outermost shell followed with (n – 1)s2p6 or (n – 1)s2 (i.e., Li).



    Lithium           or    3Li         :    1S2, 2s1 or [He] 2s1


    Sodium          or    11Na     :    1s2, 2s22p6, 3s1 or [Ne] 3s1


    Potassium    or    19K        :    1s2, 2s22p6, 3s22p6, 4s1 or [Ar] 4s1


    Rubidium      or    37Rb     :    1s2, 2s22p6, 3s23p6d10, 4s24p6d10, 5s25p6, 6s1 

                                                        or [Xe] 6s1



    Caesium       or    55Cs     :    1s2, 2s22p6, 3s23p63d10, 4s24p6d10, 5s25p6, 6s1 

                                                        or [Xe] 6s1



    Francium        or    87Fr     :    1s2, 2s22p6, 3s23p63d10, 4s24p64f14, 5s25p65d10, 6s26p6, 7s1 
                                                         or [Rn] 7s1





2.    Because of similarity in electronic configuration, they exhibit similar properties. A regular gradation in their properties with increase in at. no. is observed due to increasing size of atoms/ions and the low binding energy of valency electrons.



3.    Of all the alkali metals, only sodium and potassium are found in abundance in nature. Francium occurs only in minute quantities as a radioactive decay product.

    Physical Nature



Some important ores of alkali metals are as follows:

        

Lithium         :    Tiphylite, Petalite, Lepidolite, Spodumene, [LiAl(SiO3)3],     Amblygonite [Li(AIF)PO4]


Sodium        :    Chile salt petre (NaNO3), Rock slt or Sodium chloride (NaCI), Sodium sulphate (Na2SO4), Borax (Na2B4O7.10H2O),
                          Glauber salt (Na2SO4.10H2O), Natron (Na2CO3.HO), Soda Felspar (NaAISi3O8), Cryolite (Na3AI6) and Trona 
                          (Na2CO3.2NaHCO3.3H2O).      
   

Potassium    :    Sylvine (KCI), carnallite (KCI.MgCI2.6H2O), Felspur (K2O.AI2O3.6SiO2), Polyhalite (K2SO4.MgSO4.CaSO4.6H2O), Indian salt 
                             peter (KNO3) and Kainite (KCI.MgSO4.MgCI2.3H2O).  
                     

Rubidium     :    Lepidolite, triphylite Lithium ores contains 0.7 to 3% Rb2O.


Caesium     :    Lepidolite, Pollucite contains 0.2 to 7% Cs2O
						

							
characteristics:
1. they are metallic in nature and are electropositive in nature.
2.they form ionic compounds(Li is sometimes an exception)
3.they always exhibit +ve oxidation state.
ores:
1.dolomite
2.carnallite
3.rock salt
priyanka