An ideal gas at STP occupies 0.03L and has a mass of 0.002g. Which of the following gives the correct expression for the molar mass of the gas?
A) 22.4 x 0.03 / 0.002
B) 0.03 x 0.002 / 22.4
C) 22.4 x 6.02 x 1023 / 0.002
D) 22.4 x 0.002 / 0.03
Explanation
Molar mass is given in g/mol so we must simply re-arrange the units given to get g/mol. The MCAT also wants us to remember that at STP, one mole of gas occupies 22.4L.
Thus the right answer is (D):
22.4 L / 1 mol x 0.002g / 0.03L = 22.4 x 0.002 / 0.03 g/mol
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.
Related Posts
Search the Blog
Free Consultation
Interested in our Online MCAT Course, One-on-One MCAT Tutoring or Med admissions packages? Set up a free consultation with one of our experienced Senior Student Advisors.
Schedule NowPopular Posts
-
-
MCAT Blog What's on the MCAT? -
-
-
MCAT Blog How to Review MCAT Full Lengths
Free MCAT Practice Account
Need 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