Typical cut scene. These scenes are shown once to develop the story and lead up to the puzzles that need to be solved.
Players have to create salts by dropping acids onto bases and vica versa.
Of course, there's a time limit. This is a good flash-card type puzzle for recognizing acids, bases and salts. This puzzle is based on kinetics. Red fluid drains through three valves with different flow rates and is recycled back to the top container after valve C. Students must arrange the valves in the correct order so that the bottom left container fills in the specified time. An understanding of the concepts involved will yield a solution within one or two tries.