We can qualitatively predict the pH of a salt solution. Salts of strong bases an
ID: 480557 • Letter: W
Question
We can qualitatively predict the pH of a salt solution. Salts of strong bases and strong acids give neutral (pH = 7) solutions. e.g. NaCl is a salt of NaOH (strong base) and HCl (strong acid) Salts of strong bases and weak acids give basic (pH > 7) solutions. e.g. NaOCH3 is a salt of NaOH (strong base) and HOCH3 (weak acid) Salts of weak bases and strong acids give acidic (pH < 7) solutions. e.g. NH4Cl is a salt of NH4OH (weak base) and HCl (strong acid) Predict the pH of an aqueous solution of CaHPO4:
Explanation / Answer
CaHPO4 pH>7
CaHPO4 is formed from Ca(OH)2 (strong base) and H3PO4 (weak acid). Therefore the pH of aqueous solution is above 7. CaHPO4 aqueous solution pH is basic.