A 3.24-L flask is filled with propane gas (C3H8), at 1.00 atm and -13.5°C. What is the mass of the propane in the flask?

To determine the mass of propane in the flask, we need to use the ideal gas law equation:

PV = nRT

Where:
P = pressure (in atm)
V = volume (in liters)
n = number of moles
R = ideal gas constant (0.0821 L·atm/(mol·K))
T = temperature (in Kelvin)

First, we need to convert the given values to appropriate units.

1. Convert temperature from Celsius to Kelvin:
T = -13.5°C + 273.15 = 259.65 K

2. Calculate the number of moles using the ideal gas law equation:
n = PV / RT

Plugging in the known values:
n = (1.00 atm) * (3.24 L) / ((0.0821 L·atm/(mol·K)) * (259.65 K))
n = 0.136 mol

Now, we can calculate the mass of propane (C3H8) using its molar mass:

1 mole of C3H8 = 3(12.01 g) + 8(1.01 g) = 44.11 g

So, the mass of propane in the flask is:
mass = n × molar mass
mass = 0.136 mol × 44.11 g/mol
mass = 5.99 g

Therefore, the mass of the propane in the flask is approximately 5.99 grams.

Use PV = nRT and solve for n = number of mols. Then n = grams/molar mass and solve for molar mass.