That statement is true
it was easy to organize 'all' the elements in a group of threes because back then they only knew about 15 - 20 elements
hope this helps
        
                    
             
        
        
        
Answer:
As the Bohr's fixed orbit gives precise information about the radial position and momentum of the orbit, it is against the Heisenberg uncertainty principle. Thus it is inferred that the Heisenberg uncertainty principle goes and the concept Bohr's fixed Orbit are opposite to each other.
Explanation:
 
        
             
        
        
        
Answer:
Sorry mate! I can't understand this language... 
 
        
             
        
        
        
Ch = sh = why and find the stuff 
 
        
             
        
        
        
Answer: 0.055 moles of  are produced by the reaction of 0.055 mol of ammonium perchlorate.
 are produced by the reaction of 0.055 mol of ammonium perchlorate.
Explanation:
The balanced chemical reaction for decomposition of ammonium perchlorate is:
 
  
According to stoichiometry :
2 moles of  produce = 2 moles of
 produce = 2 moles of  
Thus 0.055 moles of  will produce =
 will produce = of
 of  
Thus 0.055 moles of  are produced by the reaction of 0.055mol of ammonium perchlorate.
 are produced by the reaction of 0.055mol of ammonium perchlorate.