Free notes of P block nitrogen compounds family .

• The elements of this nitrogen group is collectively called  PNICOGENS and their compounds are PNICONIDES.                                 
• Nitrogen is the most aboundant gas in atmosphere.                                                              
• Phosphorus is most reactive elements in these group and its colour is yellow ,these form is more reactive form of phosphorus. Which always kept under the water.                 
• General electronic configuration :- ns2,np3.               
• In these group the elements have np3 which is outermost orbit and have exactly halffilled so these elements have fairly stability and hence these are inert elements. Eg . N is behave a inert elements.     
• States of the elements in group:- nitrogen- gas , phosphorus:- solid vapourise easily , arsenic , Sb, Bi  :- solid .                                         
• Atomic size is increases down the group .         
• The I.E energy is more than the group 14 . Elements ,.                                                                   
• I.E is decreases the down the group.                    
• E.N is decreases the down the group.                 
• This group have E.N is more than the group 14 because of the halffilled outermost orbit so they are more stable.                                         
• Due to increases in size and decrease in EN so their metallic character is increases down the group.                                                      
• Note :-  basic nature is inversely proportional to the bond angle.                           
• Phosphorus, arsenic , antimony does not exist in diatomic molecules form , due to formation of the pπ - pπ bond between them.                                                                           
• The melting point of this group is decreases upto the arsenic and then increase upto bismuth.                                                                    
• Boiling point is increases down the group upto the bismuth. Exception Bi <Sb.                        
• All shows allotropes but exception the bismuth does not show the allotropic nature.                                                                       
• Nitrogen have two solid and one gas allotropes.                                                                  
• Phosphorus have five allotropes eg yellow red violet etc.                                                            
• White phosphorus is extract from the rock phosphate ( Ca3(Po4) ,SiO2 , coke).  When the it exposed with the air it turns into the yellow.                                                                       
• Red phosphorus is obtained from the heating yellow phosphorus in presence of the inert gases.                                                         
• Arsenic has 3 allotropes grey yellow black they have chair form structure.                           
• Group 15 shows the +3 and +5 oxidation state down the group the +3 oxidation state stability increases.                                                  
• This group shows the catenation property .     
• Black phosphorus is good conductor of the electricity.                                                                    
• White phosphorus shows the phosphorence property but red phosphorus does not show these property.                                                                
• Hydrides of the group15 has pyramidal shape bond angle decreases and boiling point is decreases down the group .                     
• Order of the basisity of hydrides of group 15   NH3 > PH3 > AsH3 > SbH3 .