Summary of Inorganic Functions: Nomenclature of Acids

Goals

1. Gain a clear understanding of acid nomenclature according to IUPAC standards.

2. Accurately name acids, distinguishing between binary and oxygen-containing types.

3. Utilise IUPAC nomenclature to tackle problems involving acid identification.

4. Hone your technical communication skills when discussing chemical compounds.

Contextualization

Acids are all around us, from the citric acid found in citrus fruits to hydrochloric acid, which is commonly used in various industrial processes. Being able to correctly use acid nomenclature is vital for identifying these substances accurately, whether you’re in a laboratory setting, manufacturing chemical products, or working in broader industry environments. For instance, hydrochloric acid (HCl) is essential for metal cleaning and organic compound production, while sulfuric acid (H2SO4) plays a key role in the production of fertilizers and in petroleum refining.

Subject Relevance

To Remember!

Definition of Acids According to IUPAC

The International Union of Pure and Applied Chemistry (IUPAC) defines acids as substances that release H+ ions (protons) when dissolved in water. This foundational definition is indispensable for identifying and naming acids correctly and falls in line with an international standard that promotes effective scientific communication.

• Acids release H+ ions in solutions.

• IUPAC provides a standard for acid nomenclature.

• Enhances communication in science and industry.

General Rules for Acid Nomenclature

The rules outlined by IUPAC for acid nomenclature require the identification of oxygen in the acid's composition. Acids are classified into two categories: binary (lacking oxygen) and oxygen-containing (with oxygen) acids, each following specific naming conventions.

• Binary acids: made up of hydrogen and a non-metal element.

• Oxygen-containing acids: consist of hydrogen, oxygen, and a non-metal element.

• Use of the suffixes 'hydric' and 'ous/ic' to name binary and oxygen-containing acids, respectively.

Nomenclature of Binary Acids

Binary acids consist of hydrogen combined with a non-metal element. These are named by adding the suffix 'hydric' to the non-metal's name, preceded by ‘acid’. For example, HCl is known as hydrochloric acid.

• Made of hydrogen and a non-metal.

• The suffix 'hydric' appears in the acid's name.

• Example: HCl is hydrochloric acid.

Nomenclature of Oxygen-Containing Acids

Oxygen-containing acids include hydrogen, oxygen, and a non-metal element. Their nomenclature is dependent on the number of oxygen atoms present. The suffix 'ous' is for acids with fewer oxygen atoms, while 'ic' denotes those with more. For instance, H2SO3 is termed sulfurous acid, and H2SO4 is sulfuric acid.

• Includes hydrogen, oxygen, and a non-metal element.

• 'ous' signifies fewer oxygen atoms and 'ic' indicates more.

• Example: H2SO4 is sulfuric acid.

Practical Applications

• Hydrochloric acid (HCl) is widely used for metal cleaning and in the synthesis of organic compounds.

• Sulfuric acid (H2SO4) is crucial in the production of fertilizers and petroleum refining processes.

• Acetic acid (CH3COOH) is commonly used in the food industry as a preservative and flavouring agent.

Key Terms

• Binary Acid: An acid comprising hydrogen and a non-metal element.

• Oxygen-containing Acid: An acid made of hydrogen, oxygen, and a non-metal element.

• IUPAC: The International Union of Pure and Applied Chemistry, responsible for standardizing chemical nomenclature.

Questions for Reflections

• What impact does proper acid nomenclature have on safety and efficiency in a chemist’s work?

• What could be the consequences of errors in acid nomenclature within chemical and pharmaceutical sectors?

• How does IUPAC's standardization of nomenclature benefit global scientific communication?

Practical Challenge: Naming Acids in Everyday Life

This mini-challenge is designed to reinforce your understanding of acid nomenclature rules by applying them to real-life examples and common compounds encountered in daily life and industry.

Instructions

• Team up with a classmate.

• Each pair should select three common acids (one binary and two oxygen-containing) found in everyday life or industry.

• Look up the chemical formulas for these acids and name them according to IUPAC standards.

• Prepare a short presentation (2-3 minutes) detailing the naming process for each chosen acid, emphasising the importance of correct identification in practice.

• Share your findings with the class.