MCAT Chemistry Question — Ideal Gases
- May 20, 2018
- MCAT Question of the Day
If a gas occupies 0.1L at 200atm, what will its volume be at 1atm?
A. slightly less than 20L
C. slightly more than 20L
Click for Explanation
Ideal gases undergoing pressure and volume changes are related by the expression P1V1/T1=P2V2/T2. Here, temperature is not involved and P1V1= P2V2. However, since P1 is greater than 10atm, the size of the molecules cannot be ignored and volume V1 is slightly greater than it should be for an ideal gas. Therefore, the calculated volume V2=20L is slightly larger than it should be. Choice A is correct.
A. slightly less than 20L, correct.
B. 20L, incorrect, The initial volume at a pressure of 200atm includes a small contribution from the molecules themselves, and therefore the initial volume of 0.1L is larger than the volume of an ideal gas.
C. slightly more than 20L, incorrect, See explanations for a) and b).
D. 2000L, incorrect, This answer choice incorrectly divides the initial pressure by the initial volume.
Want more MCAT practice?
We’ve got options for every schedule and learning style!
From the best online MCAT course created by top instructors with 524+ MCAT scores to the most representative full-length practice exams and private tutoring, we can custom tailor your MCAT prep to your goals!
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.
Search the Blog
Free ConsultationSchedule Now
MCAT Blog How to Review MCAT Full-Lengths
Free MCAT Practice AccountNeed great MCAT practice?
Get the most representative MCAT practice possible when you sign up for our free MCAT Account, which includes a half-length diagnostic exam and one of our full-length MCAT practice exams.Learn More