Question

Ferrophosphorus (Fe2P) reacts with pyrite (FeS2) producing iron(II) sulfide and a compound that is 27.87% P and 72.13% S by mass and has a molar mass of 444.56 g/mol.
a. Determine the empirical and molecular formulas of this compound.
b. Empirical Formula: Molecular Formula:
c. Write a balanced chemical equation for this reaction. Do not include phases.

Answer 1

Answer:

The molecular formula of the compound = $P_4S_{10}$

The empirical formula of the compound = $P_2S_{5}$

The balanced chemical equation for this reaction:

$4Fe_2P+18FeS_2\rightarrow 26FeS+P_4S_{10}$

Explanation:

Compound that is 27.87% P and 72.13% S by mass and has a molar mass of 444.56 g/mol.

Molar mass of compound = 444.56 g/mol

Number of phosphorus atom = x

Number of sulfur atom = y

Atomic  mass of phosphorus  31 g/mol

Atomic mass of sulfur = 32 g/mol

Percentage of element in compound :

$=\frac{\text{number of atoms}\times text{Atomic mass}}{\text{molar mas of compound}}\times 100$

Phosphorus :

$27.87\%=\frac{x\times 31 g/mol}{444.56 g/mol}\times 100$

x = 4

Sulfur :

$72.13\%=\frac{y\times 32 g/mol}{444.56 g/mol}\times 100$

y = 10

The molecular formula of the compound = $P_4S_{10}$

Empirical formula is the simplest chemical formula which depicts the whole number of atoms of each element present in the compound.

The empirical formula of the compound = $P_2S_{5}$

The balanced chemical equation for this reaction:

$4Fe_2P+18FeS_2\rightarrow 26FeS+P_4S_{10}$