Question

If a cylinder contains 41.8 g of CO2 in 29.5 L at 455. K, what is the pressure (in mmHg)? Be sure your answer has the correct number of significant figures.

Note: Reference the Fundamental constants and Conversion factors for non-SI units tables for additional information.

Answer 1

To find the pressure of the CO2 in the cylinder, we can use the ideal gas law equation:

PV = nRT

Where:
P is the pressure
V is the volume (29.5 L)
n is the number of moles of CO2
R is the ideal gas constant
T is the temperature (455 K)

First, we need to calculate the number of moles of CO2:
n = m/M

Where:
m is the mass of CO2 (41.8 g)
M is the molar mass of CO2 (44.01 g/mol)

n = 41.8 g / 44.01 g/mol ≈ 0.951 mol

Now we can substitute the values into the ideal gas law equation:
P(29.5 L) = (0.951 mol)(0.0821 L.atm/mol.K)(455 K)

P = (0.951 mol)(0.0821 L.atm/mol.K)(455 K) / 29.5 L
P = 11.87 atm

To convert atm to mmHg, we can use the conversion factor:
1 atm = 760 mmHg
11.87 atm x 760 mmHg / 1 atm = 9022.58 mmHg

Therefore, the pressure of the CO2 in the cylinder at 455 K is approximately 9022.58 mmHg, which should be rounded to 5 significant figures. Thus, the pressure is 9023 mmHg.