Define or illustrate the meaning of the following terms: 

a. Amphoteric 

b. K_w reaction 

c. K_w equilibrium constant 

d. pH 

e. pOH 

f. pK_w

Give the conditions for a neutral aqueous solution at 25°C, in terms of [H⁺], pH, and the relationship between [H⁺] and [OH^-]. Do the same for an acidic solution and for a basic solution. As a solution becomes more acidic, what happens to pH, pOH, [H⁺], and [OH^-]? As a solution becomes more basic, what happens to pH, pOH, [H⁺], and [OH^-]?