Hydrogen because it only has one electron
The smallest unit that can exist as an element and still have proprieties of that element is an Atom<span />
Physical. you didn't burn it or create a chemical reaction
Neither a weak acid nor a weak base has a strong tendency to transfer H+ ions that is why<span> weak acid-weak base reactions not go to completion.</span>
Complete Question
The complete question is shown on the first uploaded image
Answer:
The equilibrium constant is 
Explanation:
From the question we are told that
The chemical reaction equation is

The voume of the misture is
The molar mass of
is a constant with value of 
The molar mass of
is a constant with value of 
The molar mass of
is a constant with value of 
Generally the number of moles is mathematically given as

For 


For 


For 


Generally the concentration of a compound is mathematicallyrepresented as

For 
![Concentration[Fe_2 O_3] = \frac{0.222125}{5.4}](https://tex.z-dn.net/?f=Concentration%5BFe_2%20O_3%5D%20%3D%20%5Cfrac%7B0.222125%7D%7B5.4%7D)
For 
![Concentration[H_2] = \frac{1.815}{5.4}](https://tex.z-dn.net/?f=Concentration%5BH_2%5D%20%3D%20%5Cfrac%7B1.815%7D%7B5.4%7D)

For 
![Concentration [H_2O] = \frac{0.12}{5.4}](https://tex.z-dn.net/?f=Concentration%20%5BH_2O%5D%20%3D%20%5Cfrac%7B0.12%7D%7B5.4%7D)

The equilibrium constant is mathematically represented as
![K_c = \frac{[concentration \ of \ product]}{[concentration \ of \ reactant ]}](https://tex.z-dn.net/?f=K_c%20%3D%20%5Cfrac%7B%5Bconcentration%20%5C%20of%20%5C%20product%5D%7D%7B%5Bconcentration%20%5C%20of%20%5C%20reactant%20%5D%7D)
Considering 
And 
At equilibrium the

