This paper presents an argumentation-based demonstration experiment to teach the light-matter interaction using an observable laser beam and vacuum pump. In the experiment, the concept of darkness was addressed using a virtual space environment created by gradually decreasing the pressure inside a quartz glass bell jar with a vacuum pump. This experimental activity, offering an evidence-based inquiry, deepened the conceptual understanding of the students in relation to the light-matter interaction and other events that occurred following the decrease in the intensity of light entering the eye, caused by the reduced pressure in the vacuum bell jar.