Answer: Electronegativity increases as the size of an atom decrease.
Explanation: Electronegativity is the measure of the ability of an atom in a bond to attract electrons to itself. 
Electronegativity increases across a period and decreases down a group.
Towards the left of the table, valence shells are less than half full, so these atoms (metals) tend 
to lose electrons and have low electronegativity. Towards the right of the table, valence shells are more than half full, so these atoms (nonmetals) tend to gain electrons and have high electronegativity. 
Down a group, the number of energy levels (n) increases, and so does the distance between the nucleus and the outermost orbital. The increased distance and the increased shielding weaken the nuclear attraction, and so an atom can’t attract electrons as strongly. 
 
        
             
        
        
        
The answer is D. 459 g As
        
                    
             
        
        
        
The excess reactant is Aluminum.
<u>Explanation:</u>
We have to write the balanced equation as, 
4 Al+ 3 O₂ → 2 Al₂O₃
According to the molar ratio 4: 3, from the given balanced equation, we can say that 4 atoms of Al reacted with 3 molecules of oxygen. 
Given that 10 atoms of aluminum reacts with 6 molecules of oxygen, as per the ratio only 8 atoms of Aluminum is required to react with 6 molecules of oxygen, so excess reactant is Aluminum.
 
        
             
        
        
        
You spelled bored wrong lol
        
                    
             
        
        
        
CH2O2 formic acid I believe so