Question

a particular protein sample is found to have one atom of iron in its chemical formula. if the mass percent of fe in the compound is 0.330% fe, what is the molar mass of the protein?

Explanation:

Step1: Recall the formula for mass percent

Mass percent of an element \(=\frac{\text{mass of element in compound}}{\text{molar mass of compound}}\times100\%\)

Let the molar mass of the protein be \(M\). The mass of iron (\(Fe\)) in one mole of the protein is \(55.85\space g\) (molar mass of \(Fe\)). Given mass percent of \(Fe = 0.330\%\)

We can write the equation: \(0.330\%=\frac{55.85}{M}\times100\%\)

Step2: Solve for \(M\)

First, rewrite the equation as \(\frac{0.330}{100}=\frac{55.85}{M}\)

Cross - multiply: \(0.330M=55.85\times100\)

Then \(M=\frac{55.85\times100}{0.330}\)

$$M=\frac{5585}{0.330}\approx16924.24\space g/mol$$

Answer:

The molar mass of the protein is approximately \(16924\space g/mol\)