There are several online forums and groups where you can discuss Chemistry optional subject doubts. These platforms provide a space for students and aspirants to connect, share knowledge, and seek guidance from experts. One such platform is EduRev, which is a popular online education community that offers a dedicated section for UPSC aspirants. In this section, you can find various forums and groups related to different subjects, including Chemistry. Here's how you can utilize these resources:

1. Sign up on EduRev:
- Visit the EduRev website (www.edurev.in) and sign up for a free account.
- Fill in the required details and create your profile.

2. Join the UPSC Community:
- Once you have signed up, navigate to the UPSC section on the website.
- Join the UPSC community, which will give you access to all the relevant forums and groups.

3. Explore the Chemistry Section:
- Within the UPSC community, you will find sub-sections for different subjects.
- Look for the Chemistry section or any sub-section specific to Chemistry optional.

4. Engage in Discussions:
- Browse through the posts and discussions in the Chemistry section.
- If you have a doubt or question, create a new post with a clear and concise title.
- Provide detailed information about your doubt in the description box.

5. Seek Guidance from Experts:
- Many experienced educators and subject matter experts actively participate in these forums.
- They often provide detailed explanations and solutions to the queries posted by students.
- Be patient and wait for responses from experts or other community members.

6. Participate in Group Chats:
- In addition to forums, EduRev also offers group chat features.
- You can join relevant Chemistry groups and engage in real-time discussions with fellow aspirants.
- This allows you to interact with a wider community and get instant responses to your doubts.

Remember to follow the community guidelines and maintain a respectful and constructive approach while seeking and providing help. By actively participating in these forums and groups, you can enhance your understanding of Chemistry and clarify any doubts you may have.