**CHM 2045C Module 6 Sample
Exam**

**Module 6 Sample Answers**

**Module
Six Part B: Discussion Question 5 points**

**In the Real Gas Equation: (P + an ^{2}/V^{2})
(V - nb) = n RT a pressure correction factor was
added. Why? (What assumptions of the kinetic theory breakdown under extreme
conditions of temperature and pressure?)**

**In Section 12.9
on page 576 the answer is in the third paragraph!**

**Another
assumption of the kinetic molecular theory is that collisions between the
molecules are elastic-that is, that the atoms or molecules of the gas never
stick to one another by some type of intermolecular force. This is no true at extreme conditions of
overcrowding. When a molecule is about to strike the wall of its container,
other molecules in the vicinity exert a slight attraction for the molecule and
pull it away from the wall. As a result of the intermolecular forces, molecules
strike the wall with less force than they would in the absence of
intermolecular attractive forces. Therefore, in a real gas, the observed
pressure is less than the predicted pressure by the ideal gas law and a
pressure correction factor is added to account for this pressure loss.**

**Also a volume correction factor was
subtracted. Why? (What assumptions of the KMT breakdown under extreme
conditions?)**

**In Section 12.9 on page 576 the
answer is in the second paragraph!**

**The kinetic
molecular theory and the ideal gas law are concerned with the volume available
to the molecules to move about, not the volume of the molecules themselves. It
is clear the volume occupied by the gas molecules is NOT negligible at high
pressures (or extreme low temperatures. The available volume is less than the
volume of the container. The volume the molecules occupy must be subtracted
from the volume of the container to obtain the volume of free space the
molecule can move. **

**Module
Six-Part C Standard Conditions/Molar
Volume 5 points**

State standard
conditions (STP) in three units of pressure (the last is your choice) and ^{o}**C**** **and** K temperatures:**

_**760**__mmHg
or _**760**__torre= __**1**___atm
= Bonus: _**29.9
in**_ = _**14.7 psi**_=
**101 kPa**

__**0**_** ^{
oC}** = _

Are the values for
the Molar Gas Volume Constant:

1 mole** _{ CO2 }**=__

_{ }

_{ }

1 mole** _{ N2 }**=__