Respuesta :

This queston is not of Algebra. It is of chemistry.

You have to work with the chemical formula of the compound, the atomic and molar masses and use proportions.

1) PH3:

element     atomic mass    number of atoms    total mass
P               31 g/mol          1                             31 g/mol
H               1.0 g/mol         3                             3.0 g/mol
                                                                         ------------------
                                          molar mass             34 g/mol
2) proportions

372 g H / x = 3.0 g H / 34 g PH3

=> x = 372g H * 34 g PH3 / 3.0 g H = 4216 g PH3

Answer: 4216 g