A salt consists of the positive ion (cation) of a base substance and the negative ion (anion) of an acidic substance. For instance , neutralization reactions cause the formation of salts and water. To be more precise , salts are formed when an acidic substance react with basic substance and the reaction is known as neutralisation reaction. This reaction is used for the neutralization in the spillage of dangerous acidic substances. If we use water to extinguish the fumes when a container containing some extreme acids like sulphuric acid is spilled due to an accident, it won't help in reducing the acidity. To counter react this we have to use some alkaline solution with high pH value so that it would react with the acidic substance and leads to neutralization by the formation of salts and water. Eg : Nitric acid + potassium hydroxide -> potassium nitrate + water. Here Nitric acid reacts with basic Pottassium hydroxide to form the salt pottassium nitrate.