Question

Explain protonic concept of acids and bases with one example each.

Short answer

Question: Explain the protonic concept of acids and bases and provide an example of an acid and a base that adheres to this concept. Answer: The protonic concept of acids and bases, also known as the Brønsted-Lowry concept, defines an acid as a proton (H+) donor and a base as a proton (H+) acceptor. An example of an acid is hydrochloric acid (HCl), which donates a proton (H+) when dissolved in water. An example of a base is ammonia (NH3), which accepts a proton (H+) from water molecules when dissolved in water.

Step-by-step solution

Introduction to the Protonic Concept of Acids and Bases

The protonic concept of acids and bases, also known as the Brønsted-Lowry concept, was proposed independently by Johannes Nicolaus Brønsted and Thomas Martin Lowry in 1923. According to this concept, an acid is a substance that donates a proton (H+) to another substance, while a base is a substance that accepts a proton. The acid is called the "proton donor," and the base is called the "proton acceptor." This definition includes a broader range of acidic and basic substances than the Arrhenius concept, which defines acids as substances that produce H+ ions in water and bases as substances that produce OH- ions in water.

Example of an Acid: Hydrochloric Acid (HCl)

Hydrochloric acid (HCl) is an example of an acid according to the protonic concept. When HCl dissolves in water, it dissociates into hydrogen ions (H+) and chloride ions (Cl-). The chemical equation for this process is given below: HCl(aq) -> H+(aq) + Cl-(aq) As HCl donates a proton (H+) to water, it acts as a proton donor and thus fulfills the definition of an acid in the protonic concept.

Example of a Base: Ammonia (NH3)

Ammonia (NH3) is an example of a base according to the protonic concept. When ammonia dissolves in water, it readily accepts a proton (H+) from water molecules, forming an ammonium ion (NH4+). The chemical equation for this process is given below: NH3(aq) + H2O(l) -> NH4+(aq) + OH-(aq) As ammonia accepts a proton from water, it acts as a proton acceptor and thus fulfills the definition of a base in the protonic concept.

Conclusion

In summary, the protonic concept of acids and bases, also known as the Brønsted-Lowry concept, describes an acid as a proton donor and a base as a proton acceptor. Hydrochloric acid (HCl) and ammonia (NH3) are examples of an acid and a base, respectively, according to this concept. HCl donates a proton (H+) when dissolved in water, while NH3 accepts a proton (H+) from water molecules, making them representative examples of acids and bases under the protonic concept.

Key concepts

Proton Donor

In the fascinating world of chemistry, the term proton donor refers to any substance that can release a proton (H+), effectively acting as an acid in a chemical reaction. This idea is crucial to understand the behavior of acidic substances.

When an acid releases a proton, the remaining part of the molecule usually carries a negative charge and becomes what is known as a conjugate base. This transformation is the heart of many chemical processes, including neutralization and buffer systems in biology. To get a practical insight into what a proton donor does, think of vinegar (acetic acid) on baking soda; it's the acetic acid donating protons that makes that fizzy reaction!

Proton Acceptor

On the flip side, a proton acceptor is any substance that takes in, or 'accepts', a proton (H+), behaving as a base according to the Brønsted-Lowry theory. Understanding the role of bases in chemistry is as significant as understanding acids.

The concept of proton acceptor gives us a lens to view how substances neutralize acids or form more complex structures by gaining a proton. This acquisition turns the base into a conjugate acid. A household example could be the same scenario with baking soda; acting as a proton acceptor, it neutralizes the acid's effects, which is what makes it a common ingredient in antacids!

Hydrochloric Acid

Hydrochloric acid (HCl) is a powerful and commonly referenced example of a Brønsted-Lowry acid. It is encountered both in industrial settings and within our stomachs, where it aids digestion.

As a proton donor, hydrochloric acid is known for its tendency to release a proton to interact with other substances. This characteristic allows HCl to participate in a myriad of reactions. In aqueous solutions, hydrochloric acid demonstrates its acidic properties by dissociating into hydrogen and chloride ions, a process integral to many fields of chemistry and biochemistry.

Ammonia

On the other side of the acid-base spectrum, ammonia (NH3) is a well-known Brønsted-Lowry base and has considerable industrial and agricultural importance. In aqueous solutions, it serves as a proton acceptor, capturing a proton to form an ammonium ion (NH4+).

This reaction not only exemplifies the basic nature of ammonia but also is a cornerstone of understanding nitrogen's role in biological systems and the environment. Ammonia's ability to accept protons makes it a key player in neutralization reactions and the nitrogen cycle, a testament to the beautiful interconnectedness in chemistry.