Conceptest: Cooling and composition indicators of Igneous Rocks

David McConnell, Department of Marine, Earth, and Atmospheric Sciences, North Carolina State University
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This material is replicated on a number of sites as part of the SERC Pedagogic Service Project
Initial Publication Date: November 30, 2008

Question:

What is the most likely cooling rate and composition of a light colored, small grained igneous rock?
A. Cooled rapidly, low silica
B. Cooled rapidly, high silica
C. Cooled slowly, low silica
D. Cooled slowly, high silica

Student Responses:

These responses were collected from 200 non-majors (mostly freshmen) in multiple large (60+ students) introductory Earth Science classes at an open-enrollment Midwestern state university.
A. 6% of students chose this answer
B. 70% of students chose this answer (correct)
C. 8% of students chose this answer
D. 16% of students chose this answer

References and Notes: