A 75.0 l steel tank at 20.0°c contains acetylene gas, c2h2, at a pressure of 1.39 atm. assuming ideal behavior, how many grams of acetylene are in the tank?
we can use the ideal gas law equation to find the number of moles of acetylene gas in the tank PV = nRT where P - pressure - 1.39 atm x 101 325 Pa/atm = 140 842 Pa V - volume - 75.0 x 10⁻³ m³ n - number of moles R - universal gas constant - 8.314 Jmol⁻¹K⁻¹ T - temperature in kelvin - 20 °C + 273 = 293 K substituting these values in the equation 140 842 Pa x 75.0 x 10⁻³ m³ = n x 8.314 Jmol⁻¹K⁻¹ x 293 K n = 4.34 mol molar mass of acetylene - 26 g/mol mass of acetylene present - 4.34 mol x 26 g/mol = 112.84 g mass of acetylene present - 112.84 g
