Answer:
Noble gases are nonreactive, nonmetallic elements in group 18 of the periodic table. Noble gases are the least reactive of all elements. That's because they have eight valence electrons, which fill their outer energy level.
Elements: Argon
 
        
                    
             
        
        
        
The correct answer is C) There are more particle collision
With more particle collision, more reactions are created. 
        
                    
             
        
        
        
Its A because I did it on connexus
 
        
             
        
        
        
The first blank can be filled with the Heliocentric model, and the second blank can be filled with Copernicus.  
The heliocentric model known as heliocentrism was proposed by the Renaissance astronomer, mathematician, and the Catholic cleric Nicolaus Copernicus resulting in the Copernican revolution.  
It is the astronomical model, in which the planets and the Earth revolve around the Sun positioned at the middle of the Solar system. Factually, the heliocentric model was in contrast to geocentrism, in which Earth is positioned at the center of the Solar system.