Show Me!
How many mol of CH4 are in a 150 L
tank exerting a pressure of 20.0 atm when the temperature
is 24.0 degrees Celsius?
Problem Solving Strategy:
Since this is a problem about a gas, and all the data provided are physical
properties we conclude it is an Ideal Gas Law Problem and we need to construct
a table to associate values in the problem statement with the variables in the
Ideal Gas Law (PV = nRT).
The Table before entering the data would look like;
Completing the table with the data from the problem;
|
P
|
V
|
n
|
R
|
T
|
Condition
|
|
20.0 atm
|
150 L
|
?
|
0.0821 L atm mol-1 K-1
|
24.0 C
|
1
|
Notice there is only one condition for this gas. If there were more than one
condition we would extend the table for additional concditions. Before continuing
we must convert all the units for each variable so they correspond to the units
for R. In this problem the units on pressure and volume agree with the units
in R, but the units on temperature are in Celsius. Temperature units must be
Kelvins in any Ideal Gas Law Problem.
Click here to show the conversion
of Celsius to Kelvins.