Acids and Bases

Acids and bases are groups of substances that play an important role in chemistry and in everyday life. An acid releases hydrogen ions when dissolved in water, while a base can accept those ions or release hydroxide ions, depending on the chemical model used. Their properties can be measured with the pH scale, which usually ranges from 0 to 14.

A pH below 7 indicates an acidic solution, a pH above 7 indicates a basic or alkaline solution, and a pH close to 7 is considered neutral. Lemon juice, vinegar and many soft drinks are acidic, whereas baking soda dissolved in water and many household cleaning products are basic. Pure water is close to neutral under normal conditions.

When an acid and a base react together, they often undergo a neutralization reaction that produces water and a salt. This type of reaction is widely used in nature, industry and everyday life. Farmers sometimes add basic materials such as lime to reduce the acidity of soil, helping some crops grow better.

Doctors may recommend antacid medicines to relieve excess stomach acid. In laboratories, chemists use indicators that change color according to pH to identify whether a solution is acidic or basic. Although many acids and bases are useful, some are corrosive and can damage skin, eyes or materials, so they should always be handled carefully and with appropriate protection.