Salts That Act as Acids

Some salts act as acids. Salts that act as acids react with hydroxide ions. Ammonium chloride, NH4CI, is such a salt. This salt is also called sal ammoniac. As a flux added to solder used to solder copper plumbing or automobile radiators, ammonium chloride dissolves coatings of corrosion on the metal surfaces so that the solder can stick. In the presence of a base, NH4CI reacts with the hydroxide ion to produce ammonia gas and water  

When acids, bases, or salts are dissolved in water, charged ions are formed. When HCl gas is dissolved in water, all of it goes to H+ and Cl ions  

Acetic acid in water also forms a few ions, but most of it stays as CH3CO2H  

Sodium hydroxide in water is all in the form of Na+ and OH ions. The salt, NaCl, is all present as Na+ and Cl ions in water. 

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