Rupesh Sharma completed an investigatory chemistry project on determining which antacid neutralizes stomach acid most under the guidance of his teacher Mr. Jitendra Khandelwal. He expresses gratitude to his teacher, principal Dr. Sunita Vashistha, and parents for their support. The project involved testing common antacids like aluminum hydroxide and magnesium hydroxide in an experiment to measure their acid-neutralizing effects and determine the most effective antacid.