i believe molar mass of P4 (phosphorus) is 4 x 31 = 124 g/mol (31 is the atomic mass of phosphorus).
To find the mass of 3.01 x 10^22 molecules of P4, we need to first calculate the number of moles of P4 in 3.01 x 10^22 molecules.
Number of moles = Number of molecules / Avogadro's number
Number of moles = 3.01 x 10^22 / 6.022 x 10^23
Number of moles = 0.005
Now that we know the number of moles, we can use the molar mass to calculate the mass:
Mass = Number of moles x Molar mass
Mass = 0.005 mol x 124 g/mol
Mass = 0.62 g
Therefore, the mass of 3.01 x 10^22 molecules of P4 is 0.62 g.