Problem 18.68 Part A The size (radius) of an oxygen molecule is about 2.0 ×1010m
ID: 1510972 • Letter: P
Question
Problem 18.68 Part A The size (radius) of an oxygen molecule is about 2.0 ×1010m. Make a rough estimate of the pressure at which the finite volume of the molecules should cause noticeable deviations from ideal-gas behavior at ordinary temperatures (T= 300K ). Assume that deviatons would be noticeable when volume of the gas per molecule equals the volume of the molecule itself. Express your answer using one significant figure. P = 5•106 Pa SubmitMy AnswersGive Up Incorrect; Try Again; 5 attempts remaining Provide FeedbackContinue PH105-S004 Spring 2016 Help Close Ch 18 HW Problem 18.68 ResourcesConstants « previous 17 of 27 next »
Explanation / Answer
PV = nRT
V / (n * Na) = 4/3 pi r^3 --- Na is avocado number :^)
V = 4/3 pi * r^3 * n * Na
R = 8.3145 (it s also good to know the unit of this is m^3 Pa/mol /K which works for our purposes)
P = nRT/V = RT / (4/3 pi * r^3 * Na) = Really big number rounded to ONE sigfig = 1×10^8 Pa