we can find the number of moles of PH₃ using ideal gas law equation PV = nRTwhere P - standard pressure - 101 325 Pa V - volume - 250 x 10⁻⁶ m³ n - number of moles R - universal gas constant - 8.314 Jmol⁻¹K⁻¹ T - temperature - 273 K substituting the values in the equation 101 325 Pa x 250 x 10⁻⁶ m³ = n x 8.314 Jmol⁻¹K⁻¹ x 273 K n = 0.011 mol therefore mass of PH₃ = 0.011 mol x 34 g/mol = 0.374 g mass of PH₃ is 0.374 g
