Introduction to the Idea of Salts

 Yesterday, we concluded a rich discussion on the pH scale and we solved nine mathematical problems that relate to pH, pOH, pKb, pKa etc then I gave you one problem to figure out on your own. I am still waiting for your response to that self test question. 


Just as I announced yesterday, we are beginning a discussion of the concept of salts today. I twice mentioned when we were looking at the properties of acids and bases that formation of salts is a chemical property of both acids and bases.


In fact, a salt is formed BY THE REPLACEMENT OF THE HYDROGEN IONS IN AN ACID BY METALS IONS OR OTHER POSITIVELY CHARGED SPECIES SUCH AS AMMONIUM IONS. The preceding phrase was written in upper case for emphasis. My concern in today’s lesson is to explain this phrase so that we can all be on the same page as we proceed in this discussion.


I would list five salts and their corresponding acids and see if you can agree with the preceding paragraph after looking at the list;


Salt name               Salt formula    Corresponding acid formula 

Sodium Chloride        NaCl                             HCl

Lead II ethanoate         Pb(CH3COO)2            CH3COOH

Calcium sulphate       CaSO4                        H2SO4

Barium nitrate             Ba(NO3)2                  HNO3

Potassium carbonate     K2CO3                     H2CO3


Can you see my point after going through the list above? For instance; If you replace the H in HCl with Na, then you have the salt NaCl. The same applies throughout the list. Is this point clear?


Hope you enjoyed our lesson today?

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