At atmospheric pressure, carbon dioxide undergoes sublimation at -109.5°F. How does the entropy change when CO2 undergoes deposition?
A. ΔS>0
B. ΔS<0
C. ΔS=0
D. cannot be determined
Click for Explanation
Deposition is a phase change from gas directly to solid. Less freedom of motion for the elements in a solid translates into less entropy: ΔS<0.
A. ΔS>0, incorrect, A solid arrangement of packed molecules is lower in probability than freely moving gas particles.
B. ΔS<0, correct.
C. ΔS=0, incorrect, Gas phases have greater entropy than solid phases.
D. cannot be determined, incorrect, See answer C.
Want more MCAT practice?
We’ve got options for every schedule and learning style!
Whether you need the flexibility of a Self-Paced Course, the instruction of a live 515+ Course, or the 1:1 attention of a private MCAT tutor, Blueprint MCAT has the MCAT prep option that works for your learning style!
Get started with a free MCAT diagnostic, one free practice exam, and tons more MCAT prep resources.
Not sure which option is right for you? Schedule a free MCAT consultation with an MCAT expert using the form below. No obligation, just expert advice.
