Answer:
HCO₂/H₂O is not the acid-base conjugate pair.
Explanation:
<em>Acid and conjugate base pairs differ by an H+ ion.</em>
Neither HCO₂ nor H₂O has lost or gained protons.
The conjugate acid of H₂O is H₃O⁺
The conjugate base of HCO₃⁻ is CO₃²⁻
[A conjugate acid has one more H⁺ than its base]
 
        
             
        
        
        
Chlorine is a halogen and all halogens and oxygen, nitrogen and hydrogen are diatomics
        
                    
             
        
        
        
The molarity is calculated using the following rule:
molarity = number of moles of solvent / volume of solution (in liters)
We have the volume of solution = 250 ml = 0.25 liters and the molarity = 3 m
Substituting in the equation, we get:
3 = number of moles / 0.25
number of moles = 3 x 0.25 = 0.75 moles
        
             
        
        
        
Explanation:
When OH- (as in potassium hydroxide) is added, it reacts with the acid (HOCl) to reduce the amount of HOCl and increase the concentration of  sodium hypochlorite. 
Potassium hydroxide will react with the hypochlorous acid to produce hypochlorite ions. In the process, some of the weak acid will be consumed, along with the added strong base.
This occurs as follows: 
 HClO(aq) + KOH(aq) → KClO(aq) + H2O(l)  
since water is formed, this maintains the pH.  Thus ...
 
A. The number of moles of HClO will decrease. - TRUE
B. The number of moles of ClO- will increase. - TRUE
C. The equilibrium concentration of H3O+ will remain the same. - TRUE
D. The pH will decrease. - FALSE
E. The ratio of [HClO] / [ClO-] will decrease. -TRUE. It will decrease as HClO goes down and ClO- goes up.