This project was preformed to supply Libretext Authors with videos on General Chemistry topics which can be used to enhance their projects. Also, these videos are meant to act as a learning resource for all General Chemistry students . Video Topics When a reaction produces gas as a product it is usually collected over water. To find information about the captured gas Dalton's law of partial pressures and the ideal gas law equation is typically used. Because water evaporates it also produces a partial pressure called a vapor pressure. This video contains a sample problem involving these concepts. Link to Video Collecting a Product Gas over Water: https://youtu.be/zFuy3t81vjQ Attribution Prof. Steven Farmer ( Sonoma State University )