Answer:
Model
Explanation:
A model of anything is something you make to represent it in it's physical world form 
 
        
             
        
        
        
B) 40%  
The balanced equation indicates that for every 3 moles of H2 used, 2 moles of NH3 will be produced. So the reaction if it had 100% yield would produce (2.00 / 3) * 2 = 1.333333333 moles of NH3. But only 0.54 moles were produced. So the percent yield is 0.54 / 1.3333 = 0.405 = 40.5%. This is a close enough match to option "b" to be considered correct.
        
                    
             
        
        
        
I believe it is Sodium. I could be wrong though.
        
             
        
        
        
Answer:
True
Explanation:
Protons have a positive electrical of +1