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General Chemistry

Base

Definition and meaning of Base in chemistry.

A base is a substance that donates hydroxide ions (OH⁻) in solution or accepts protons (H⁺) according to Brønsted-Lowry theory. Bases produce solutions with pH greater than 7 at 25°C.

In more detail

Bases can be strong (completely ionize in water like sodium hydroxide) or weak (partially ionize like ammonia). Common bases include group 1 metal hydroxides and ammonia. Bases are essential in biological systems, water treatment, and industrial synthesis, where they neutralize acids in neutralization reactions that produce salts and water.

Key facts

FieldGeneral Chemistry
pH Range> 7 at 25°C
Common FormulaNaOH, NH3, Ca(OH)2
IonizationStrong bases completely ionize; weak bases partially ionize
Example

Ammonia (NH3) is a weak base commonly used in cleaning products, fertilizer manufacturing, and laboratory chemistry.

Frequently asked questions

What is the difference between a strong and weak base?

A strong base completely ionizes in water, releasing all its hydroxide ions (like NaOH). A weak base only partially ionizes, establishing equilibrium between ionized and molecular forms (like NH3).

How do bases react with acids?

Bases and acids undergo neutralization reactions, producing water and a salt. For example: NaOH + HCl → NaCl + H2O.

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