Question

A 75.0 L steel tank at 20.0 degrees C contains propane gas, C3H8, at a pressure of 1.39 atm. Assuming ideal behavior, how many moles of C atoms are in the tank?

Answer 1

volume V = 75 L

temperature T = 20 c = 293 K

pressure P = 1.39 atm

gas constant R = 0.0821 l atm / k mol

using the ideal gas equation PV =nRT

n =PV/RT

n = 1.39 * 75 / 0.0821 * 293

n = 4.3337 moles

so no fo moles of C3H8 => 4.3337 moles

1 mole of C3H8 contains the 3 moles of carbon atoms

so => 4.3337 * 3 => 13 moles

answer => 13 moles of carbon atoms