Question

A mixture at 10g of Ne and 10g Ar have a total pressure of 1.6atm. What is the partial pressure of Ne?

Answer 1

Ans. Moles of Ne = Mass / Molar mass

                                    = 10.0 g / (20.1797 g/ mol)

                                    = 0.49555 mol

Moles of Ar = 10.0 g / (39.948 g/ mol) = 0.25033 mol

# Total number of moles in mixture = Moles of Ne + Moles of Ar

                                    = 0.49555 mol + 0.25033 mol

                                    = 0.74588 mol

# Mole fraction of Ne = Moles of Ne / Total number of moles in mixture

                                    = 0.49555 mol / 0.74588 mol

                                    = 0.6644

Now,

            Partial pressure of Ne = Mole fraction of Ne x Total pressure

                                    = 0.6644 x 1.6 atm

                                    = 1.063 atm