A second order reaction varies with the square of the concentration of the reactant. Therefore, halving the concentration will reduce the rate of reaction by a factor of 4.
The answer is E.
        
                    
             
        
        
        
Answer:
Cell membrane
B
Explanation:
Capsules, fimbriae, pili, flagella, and even the cell wall 
 
        
                    
             
        
        
        
The answer is (2) higher vapor pressure and weaker intermolecular forces. Propanone has a lower boiling point, so it is more volatile than water. Propanone's vapor pressure is, therefore, higher than that of water at 50 degrees Celsius. Propanone is more volatile due to the fact that the intermolecular forces that hold its molecuels together are not as strong as those that hold together molecules of water. Since the IMFs are weaker, it takes less thermal energy to break individual molecules free of each other.
        
             
        
        
        
Explanation:
The reaction equation will be as follows.
       
Hence, the expression for  is as follows.
 is as follows.
             ![K_{a} = \frac{[H_{2}SO^{-}_{4}][H^{+}]}{[H_{3}AsO_{4}]}](https://tex.z-dn.net/?f=K_%7Ba%7D%20%3D%20%5Cfrac%7B%5BH_%7B2%7DSO%5E%7B-%7D_%7B4%7D%5D%5BH%5E%7B%2B%7D%5D%7D%7B%5BH_%7B3%7DAsO_%7B4%7D%5D%7D)
Let us assume that the concentration of both ![[H_{2}AsO^{-}_{4}]](https://tex.z-dn.net/?f=%5BH_%7B2%7DAsO%5E%7B-%7D_%7B4%7D%5D) and
 and ![[H^{+}]](https://tex.z-dn.net/?f=%5BH%5E%7B%2B%7D%5D) is x.
 is x.
            
                           x = 0.01118034 
This means that the concentration of ![[H^{+}]](https://tex.z-dn.net/?f=%5BH%5E%7B%2B%7D%5D) is 0.01118034.
 is 0.01118034.
Since, we know that the relation between pH and concentration of hydrogen ions is as follows.
               pH = ![-log [H^{+}]](https://tex.z-dn.net/?f=-log%20%5BH%5E%7B%2B%7D%5D)
                     = 
                     = 1.958
Thus, we can conclude that the pH of a 0.500 M solution of arsenic acid is 1.958.
 
        
             
        
        
        
The the last one, but isn't it c6h12o6?