Introduction

Relevance of the Topic

The inorganic functions are groups of compounds that share similar chemical properties. The study of these functions is fundamental in Chemistry, as they are essential to understand the reactivity of various compounds.

• The bases, one of the inorganic functions, are key components in nature and industry. They are present in common products such as soaps, antacids, and fertilizers, as well as in natural phenomena, such as the neutralization of acid rain when it comes into contact with the earth's surface.
• Moreover, mastering the nomenclature of bases is essential to ensure efficient communication among chemists, as it allows for the correct identification of compounds, facilitating study, research, and the development of new technologies.

Contextualization

The nomenclature of bases is situated within the broader context of inorganic functions, which in turn is an integral part of Chemistry, a science that studies the composition, structure, properties, and transformations of matter.

• The study of bases, specifically, is a natural transition after exploring acids - another inorganic function. Acids and bases have an intrinsic relationship, being essential components of the Arrhenius Electrolytic Dissociation Theory and the Brønsted-Lowry Acid-Base Reaction Theory.
• Understanding the nomenclature of bases not only reinforces the learning of these acid-base theories but also provides a broader view of Chemistry, allowing students to make associations between concepts and, consequently, advance their problem-solving and critical thinking skills within the discipline.

Theoretical Development

Components of Bases

• Hydroxides (OH-): Bases are composed of hydroxide ions, represented by the chemical formula OH-. The hydroxide gives the substance its basic character, i.e., makes the compound capable of neutralizing acids in chemical reactions.
• Metallic Cations (M+): The hydroxide is joined to a metallic cation to form a base. The metallic cation can be from various metals, each with its own properties and characteristics.

Key Terms

• Base: In chemistry, a base is a substance that, in aqueous solution, releases hydroxide ions (OH-). They are also called "alkaline" and can be classified as strong or weak, depending on the degree of dissociation in the solution.
• Hydroxide: It is the anion (ion with a negative charge) formed by hydrogen (H) and oxygen (O), with the formula OH-. It is an essential component of bases.
• Cation: Cations are positively charged ions. In bases, a metallic cation joins the hydroxide anion to form the compound.

Examples and Cases

• NaOH (Sodium Hydroxide): Sodium hydroxide is a strong base widely used in various applications, such as paper manufacturing, detergents, and biodiesel production. Its aqueous solution, also known as caustic soda, is highly alkaline.
• KOH (Potassium Hydroxide): Potassium hydroxide is another strong base, widely used in soap manufacturing, biodiesel production, and medicines. Like NaOH, its aqueous solution is highly alkaline.
• Ba(OH)2 (Barium Hydroxide): Barium hydroxide is an example of a strong base that has a bivalent metallic cation. It is commonly used in chemical assays and in the preparation of other chemical substances, such as barium salts.
• Al(OH)3 (Aluminum Hydroxide): Aluminum hydroxide is an example of a weak base. It is used in antacids due to its ability to neutralize excess acid in the stomach.

Detailed Summary

Relevant Points

• Definition of Bases: Bases are chemical substances belonging to the inorganic functions that, in aqueous solution, release the hydroxide anion (OH-). Such substances have an alkaline character, are capable of reacting with acids, and produce salt and water.
• Structure of Bases: Bases are formed by the combination of hydroxide (OH-) with a metallic cation (M+). The hydroxide is the component that gives bases their basic characteristics, and the metallic cation defines the specific chemical properties of the base.
• Importance of Nomenclature: The nomenclature of bases is fundamental for identifying and efficiently communicating chemical compounds. Mastery of nomenclature allows identifying the metallic element present in the base and, consequently, inferring its chemical properties.

Conclusions

• Identification of Bases: The presence of hydroxide (OH-) in the chemical formula is an indication that the substance is a base.
• Classification of Bases: Bases can be classified as strong or weak, depending on the degree of dissociation in the solution. The strength of bases is directly linked to their ability to release hydroxide ions (OH-) in the solution.
• Application of Knowledge: Correct nomenclature of bases is valuable not only in the academic context but also in the industry and everyday life, where these substances are frequently used.

Exercises

1. Identification of Bases: Given the chemical formula of a substance, determine if it is a base: (a) NaCl; (b) H2O; (c) NaOH; (d) HNO3. Justify your answers.
2. Classification of Bases: Classify the following bases as strong or weak: (a) Ba(OH)2; (b) NH4OH; (c) KOH; (d) Al(OH)3. Explain your classification.
3. Nomenclature of Bases: Write the nomenclature of the following bases: (a) LiOH; (b) Ca(OH)2; (c) Fe(OH)3; (d) Zn(OH)2.