Step-by-step explanation
(a) magnesium sulfate.
The chemical formula for magnesium sulfate is MgSO₄
From the Periodic table, the Molar Mass of:
Mg = 24.305 g/mol
O = 15.999 g/mol
S = 32.065 g/mol
So, the molar mass of MgSO₄ is calculated as follows:
MgSO₄ = (Mg + S + (4 x O))
MgSO₄ = (24.305 + 32.065 + (4 x 15.999)) g/mol
MgSO₄ = (56.37 + 63.996) g/mol
MgSO₄ = 120.366 g/mol
The molar mass of magnesium sulfate (MgSO₄) is 120.366 g/mol.
(b) diphosphorus heptoxide.
The chemical formula for diphosphorus heptoxide is P₂O₇
From the Periodic table, the Molar Mass of:
P = 30.973762 g/mol
O = 15.999 g/mol
So, the molar mass of P₂O₇ is calculated as follows:
P₂O₇ = 2(P) + 7(O)
P₂O₇ = ((2 x 30.973762) + (7 x 15.999)) g/mol
P₂O₇ = (61.947524 + 111.993) g/mol
P₂O₇ = 173.941 g/mol
The molar mass of diphosphorus heptoxide (P₂O₇) is 173.941 g/mol.
(c) iron (III) hydroxide.
The chemical formula for iron (III) hydroxide is Fe(OH)₃.
From the Periodic table, the Molar Mass of:
H = 1.00784 g/mol
O = 15.999 g/mol
Fe = 55.845 g/mol
So, the molar mass of Fe(OH)₃ is calculated as follows:
Fe(OH)₃ = Fe + 3(O) + 3(H)
Fe(OH)₃ = (55.845 + 3(15.999) + 3(1.00784)) g/mol
Fe(OH)₃ = (55.845 + 47.997 + 3.02352) g/mol
Fe(OH)₃ = 106.866 g/mol.
The molar mass of iron (III) hydroxide (Fe(OH)₃) is 106.866 g/mol.