This study examines the use of inquiry-based instruction to promote the understanding of critical concepts in thermodynamics and heat transfer. Significant research shows that students frequently enter our courses with tightly held misconceptions about the physical world that are not effectively addressed through traditional instruction. Students' conceptual understanding can be dramatically enhanced through a shift in teaching that incorporates inquiry-based methods. This work seeks to adapt inquiry-based methods to address nine critical concepts in chemical engineering thermodynamics and heat transfer. This paper traces the development of one inquiry-based activity for the equilibrium vs. steady-state concept area from its start as a concept-question to its realization as an activity.