What Does Neutralization Mean?

Neutralization is all about finding a balance between materials. In chemistry, a neutralization reaction is the reaction that happens between an acid and a base. There are all kinds of different ways that that these reactions happen both in scientific labs and in the wider world.

In chemistry, all chemical compounds are measured on a pH, or "potential of Hydrogen" scale. The scale measures from 0 to 14. Corrosive substances such as acids and bases are defined by the amount of hydrogen ion activity they give off when dissolved in water, and then the substances are separated into two categories. Those that measure from 0 to almost 7 are considered acids, and those from just above 7 to 14 are considered bases.

Sitting right at a pH level of 7 is pure water. An acidic substance lower than 7, then, breaks apart in water to form a positive hydrogen ion in that water. Common strong acids include hydrochloric acid, nitric acid and sulfuric acid.

Bases, at a pH level higher than 7, form a negatively charged hydroxide ion when they break apart in water. Common bases include sodium hydroxide and potassium hydroxide.

The term neutralization refers to a situation in which a reaction occurs that produces a solution with no excess of hydrogen or hydroxide ions. Each substance starts with its own characteristics that put it in the acid or base category. But when they come together in a neutralization reaction, the acids and bases cancel each other out to produce a neutral substance with a pH balance of 7.

The most natural form of a neutralization reaction looks like the equation for pure water, which is:

Acid + Base → Water + Salt

Keep in mind that in chemistry, salt doesn't simply refer to the stuff you sprinkle on your food. There, it simply refers to the compound that can be created by the neutralization reaction between an acid and a base.

But neutralization reactions can refer to more than just water. There are plenty of practical neutralization techniques that people use to balance substances to make everyday life a little easier. For instance, most plants cannot grow well in soil that is naturally acidic. So, farmers add fertilizers that are heavy in bases such as limestone to neutralize the acidity of the soil.

Antacid medication is another example of neutralization. People turn to these over-the-counter medications when they are experiencing heartburn or indigestion. Heartburn is a bit of a misnomer, since it is actually caused by an excess of stomach acids, not by any irregularity in your heart. A wide variety of food and drinks, including red wine, spicy foods, citrus and caffeine can all cause stomach acid to build up in some people. Popular antacids on the market, such as Alka-Seltzer, Milk of Magnesia and Pepto-Bismol all treat stomach acid with a dose of weak, easily digestible bases to neutralize the extra acid in your stomach. The most common ones used are hydroxides, carbonates and bicarbonates.