Because so much information is now available online, websites are a huge category. Be sure you are using science or government websites. How can you tell?
Additionally, think about evaluating the overall quality of the website information, using many of the same techniques as news evaluation.
Depending on your topic and research questions, you may use various government information from agencies like the US Department of Agriculture, US Geological Survey, Environmental Protection Agency, or Food and Drug Administration.
The resources below are examples. While the resources below will give you some ideas of quality science websites, there are many more out there. Peer-reviewed journals in chemistry may also have a website with a "news" or "blog" section. If you have any questions or want to talk more about potentially using a science website in your project, contact me or your professor.