The Basic Solution Is Highly Diluted

When the basic solution is highly diluted, the base behaves like a strong base and using the following general relation is legitimate  

It is interesting to note that all the relations given in this section are found in either the Arrhenius or Brpnsted theory. 

Exercise 1 Calculate the pH of a sodium cyanide solution of analytical concentration C. 

Sodium cyanide is a salt. It is completely dissociated in water. The obtained sodium ion is indifferent from an acido-basicity standpoint. The cyanide ion, however, exhibits a basic character due to its reaction with water, sometimes called a hydrolysis reaction  

It is precisely because of this reaction that the cyanide ion is basic in water. The relations that must be satisfied are 

---