Consulting reference sources is a great way to start your research. Remember that most professors will not accept work that uses information from Wikipedia. Many of the library reference sources are available online.
Citing sources is a required part of any research project. If you fail to cite or cite properly, consequences can be severe. MU Libraries have prepared some quick guides to the most common citation styles and have identified resources that assist in preparing citations.
There are many sites online that have Periodic Tables for your reference. Below is a link to the The Best 55 Online Periodic Tables: