Use this set of practice problems with answers to show students how to identify variables in a gas problem. Students will use the Combined Gas Law to solve for a missing variable, identify the correct units, and round significantly. Students will also review conceptual gas concepts such as "according to Boyle's Law, when the pressure is held constant and the temperature increases, the volume will also increase." Boyle's Law, Charles' Law, and Gay-Lussac's Law are reviewed. Lastly, students will