Question
                         
                            The diagram shows a model of an atom. The model has four different symbols on it. Each symbol represents
                         
                            different role for one of the particles within the atom.
                         
                            Model Atom
                         
                            In this model, which particle determines the reactivity of this atom?
                        
                    
                 
             
            
                
                    
                        
Answer
                        The nucleus, represented by the symbol in the center of the model, determines the reactivity of the atom.