The validation of a conceptual reasoning inventory for introductory thermodynamics

Thermodynamics is a particularly challenging course for many engineering students early in their college education. Thus, it represents a significant opportunity for the use of concept inventories to assess students' understanding of core ideas and principles in order to gauge their initial knowledge and aid their future learning. In this paper we forward an inventory to assess students' understanding of foundational thermodynamics concepts and principles, such as state relations, heat, work, and conservation of energy, as well as their ability to reason conceptually using this knowledge. A 36-item thermodynamics conceptual reasoning inventory (TCRI) was developed and evaluated. The inventory was reviewed by four external experts and administered to 448 students. This study reports evidence to demonstrate that TCRI scores are a reliable and valid indicator of students' thermodynamics conceptual knowledge and reasoning ability. TCRI scores show high internal consistency, distinguish between cohorts expected to differ, and correlate with course assessments. The TCRI is recommended for students beginning their study of thermodynamics. Course instructors can use theTCRIas a formative assessment. The TCRI can also serve as an assessment tool for researchers to evaluate the effects of instructional interventions.