This qualitative study investigated the experience of a cohort of students exposed consecutively to two substantially different environments in their General Chemistry Laboratory programme. To this end, the first semester in a traditional expository programme was followed by a semester in a cooperative, problem-based, multi-week format. The focus on the experience of a change in the laboratory format is complementary understanding to that from participants exposed to a single format. This work used a phenomenological approach for the reduction, analysis, and interpretation of data gathered from semi-structured student interviews. Through deep analysis, five researchers distilled an outcome space with three fundamental features: (1) ten vectors of change that served as lens to analyse the phenomenon; (2) participants' ability to accurately characterise and differentiate the two instructional environments; and (3) an overarching descriptor that argues that a transition from mindless behaviour to mindful engagement subsumed the experience of a change in the laboratory environment. This outcome space is independent of participants' instructional style preferences. Findings from this work inform the design of laboratory experiences furthering the potential realisation of experimental education at the same time when they extend understanding of learning in the chemistry laboratory.