Question

Which substance has the lowest [H+] concentration but is still considered an acid?

Answer 1

Answer:

                  Milk

Explanation:

                     The pH of all given substances is as follow;

                                       Milk  =  6.5 to 6.7

                                       Blood  =  7.35

                                       Gastric Fluid  =  1.5 to 3.5

                                       Household Lye  =  13.5

Therefore, we can exclude Blood and Household Lye because there pH is greater than 7 hence, they are either neutral (Blood) or Basic (Household Lye) in nature. Now, we are left with Milk and Gastric Fluids.

As we know greater the concentration of H⁺ ions, smaller is the pH hence, gastric fluid having less pH than Milk will contain more H⁺ ions therefore, more acidic than Milk. While, Milk containing less H⁺ ions (greater pH than Gastric fluid) is less acidic and contains less number of H⁺ ions.

Answer 2

the correct answer is a, milk