Question

On strong heating, boric acid yields (a) \(\mathrm{B}_{2} \mathrm{H}_{6}\) (b) \(\mathrm{B}\) (c) \(\mathrm{BO}_{2}\) (d) \(\mathrm{B}_{2} \mathrm{O}_{3}\)

Short answer

The correct answer is (d) \( \mathrm{B}_{2}\mathrm{O}_{3} \).

Step-by-step solution

Understand the Reaction

Boric acid, known chemically as \( \text{H}_3\text{BO}_3 \), decomposes upon strong heating. Our task is to predict the primary product of this decomposition.

Recognize Common Products

When boric acid \( \text{H}_3\text{BO}_3 \) is heated, it typically decomposes to form boron oxide \( \text{B}_2\text{O}_3 \) and water.

Identify the Correct Option

Given the decomposition of \( \text{H}_3\text{BO}_3 \) into \( \text{B}_2\text{O}_3 \) upon heating, the correct answer is \( \text{B}_2\text{O}_3 \), corresponding to option (d).

Conclusion

On strong heating, boric acid yields \( \text{B}_2\text{O}_3 \), which eliminates the need to consider other potential products in this specific context as they do not typically form under these conditions.

Key concepts

Boric Acid Decomposition

Boric acid, chemically represented as \( \text{H}_3\text{BO}_3 \), undergoes decomposition when subjected to high temperatures. This process, known as thermal decomposition, involves breaking down the compound into simpler substances when heated.
Understanding this decomposition is crucial because it explains how compounds like boric acid change under heat. For boric acid, the breakdown occurs due to the loss of water molecules, leading to a transformation into different products.
In a typical decomposition reaction:

• Boric acid \( \text{H}_3\text{BO}_3 \) loses water.
• The reaction can be represented as: \( \text{H}_3\text{BO}_3 \rightarrow \text{B}_2\text{O}_3 + 3\text{H}_2\text{O} \).

Recognizing the products of boric acid decomposition is essential in predicting and analyzing reactions in industrial processes and laboratory settings. Understanding this reaction also lays a foundation for learning about other thermal decomposition reactions in chemistry.

Boron Oxide Formation

During the strong heating of boric acid, the primary product formed is boron oxide. Boron oxide is represented chemically as \( \text{B}_2\text{O}_3 \). This compound is crucial in various industrial applications, including glass production and as an adhesive in some reactions.
Boron oxide formation can be understood as follows:

• When \( \text{H}_3\text{BO}_3 \) is heated, it transforms into \( \text{B}_2\text{O}_3 \), a white solid.
• This transformation involves the removal of water, making boron oxide an anhydrous compound.

Understanding boron oxide is beneficial because:

• It is used in creating borosilicate glass, resistant to thermal shock.
• It serves as an intermediary in synthesizing other chemical compounds involving boron.

Recognizing the conditions under which boron oxide forms helps in its application and manipulation in real-world chemical processes.

Thermal Decomposition Process

Thermal decomposition is a process by which a chemical compound breaks down into simpler substances when exposed to high temperatures. This process is common in many chemical reactions and is particularly applicable to the thermal stability of compounds.
In the context of boric acid:

• The compound decomposes when heated, undergoing a chemical change.
• This type of reaction is endothermic, meaning it absorbs heat energy from its surroundings to occur.

Thermal decomposition is significant because:

• It helps predict the behavior of compounds when subjected to heat.
• It provides insight into energy changes during a reaction.

Students learning about thermal decomposition should focus on its applications and implications in chemistry. Both in understanding reaction mechanisms and anticipating the properties of new products formed from existing compounds.