30POINTS PLEASE HELP ASAP

The number to the right of an element's symbol (ex. c-12) identifies the of an isotope.

The valence of aluminum is +3, and the valence of the chlorine is -1. the formula fir the aluminum chloride is correctly written as

Essay-alternative energy sources research sources of energy that are being developed. write a report of 350-400 words discussing the information you learned concerning the development of various energy sources and the impact that you think they will have on your life. include sources cited at the end of your report using the mla format. follow the rubric guidelines. note that wikipedia is not an appropriate resource for a research paper. worth 99