Answer No 1:
The chemical model that is flawed is:
4 C2 + S8 → 4 CS2
In this reaction, there are more number of carbon atoms in the reactants but lesser number of cabon atoms in the products. For a reaction to be balanced, there should be the same number  of atoms in the reactants and products. Hence, option A does not represent a balanced equation.
<em>Answer No 2:</em>
The correct option is B) The model shows an unbalanced number of carbon atoms.
 Consider the equation:
4 C2 + S8 → 4 CS2
In the reactants side of the equation, there are 8 atoms of carbon. In the products side there are only four carbon atoms. This shows that this equation in not balanced because of the carbon atoms. 
The number of sulfur atoms remains same before the reaction and after the reaction. There are eight sulfur atoms in the reactants as well as products. 
 
        
             
        
        
        
Concept: According to the basic concept of the electronic configuration of the element, the electron can be filled first in those shell which has least energy or (n +l) value. Here, n is the principal quantum number on shell and l is the azimuthal quantum number.
Since, the first shell has least value of energy in any atom. So, it should be filled first. 
Hence, the correct statement can be written as;
 When diagramming an atom, the electron shells _nearest to _ the nucleus must be filled first.
 
        
             
        
        
        
ok im not full sure man but i would say multiple voltaic cells that have spontaneous half reactions
       
                                           im sorry hope it helps
 
        
                    
             
        
        
        
Answer: El HEXAHIDRATO DE SULFATO DE NÍQUEL es incompatible con ácidos fuertes, azufre, Ni (NO3) 2, madera y otros combustibles. (NTP, 1992) A temperatura elevada sufre una reacción violenta con aluminio o magnesio en polvo. Cuando se calienta hasta la descomposición emite humos muy tóxicos de óxidos de azufre 
Explanation: