Environmental chemistry is a branch of chemistry that deals with the study of chemical processes that occur in the environment and their impact on living organisms. It is an interdisciplinary field that combines concepts from chemistry, biology, geology, and other related sciences. When answering questions related to environmental chemistry, it is important to provide examples or case studies that illustrate the concepts and principles being discussed. Here are some reasons why using examples and case studies is beneficial:

1. Enhances understanding:
Using examples and case studies helps to illustrate complex concepts and make them easier to understand. By providing real-world scenarios, it allows the reader to grasp the application of environmental chemistry in various situations.

2. Provides context:
Examples and case studies provide a context for the concepts being discussed. They help to highlight the relevance and importance of environmental chemistry in solving environmental problems and addressing issues such as pollution, climate change, and toxicology.

3. Supports arguments:
Examples and case studies can be used to support arguments and demonstrate the validity of a particular viewpoint. By presenting evidence and data from real-life situations, it strengthens the credibility of the response and adds weight to the argument being made.

4. Illustrates cause and effect:
Many environmental issues are complex and involve multiple factors. By using examples and case studies, it becomes easier to demonstrate the cause and effect relationships between different chemicals, pollutants, and their impact on the environment and human health.

5. Engages the reader:
Using examples and case studies makes the response more engaging and interesting for the reader. It helps to capture their attention and maintain their interest throughout the answer. This can be particularly important for competitive exams like UPSC, where the ability to present information in an engaging manner is valued.

In conclusion, using examples and case studies related to environmental chemistry in answers helps to enhance understanding, provide context, support arguments, illustrate cause and effect relationships, and engage the reader. By using real-life scenarios, it brings the concepts of environmental chemistry to life and demonstrates their relevance in solving environmental problems.