Answer: solvent
solvent is A solvent is usually a liquid
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
Steam is the gaseous phase of water. It is used in some cases to melt ice. Melting of ice is the conversion of solid water to liquid water. This is just a phase change in which water changes its state from solid state to liquid state. But the chemical composition of water 
remains unchanged. Water has the same molecular formula in both the solid (ice) and liquid states. Hence, the conversion of solid ice to liquid water by steam refers to a physical change.
