Cytochrome c is an iron-containing enzyme found in the cells of all aerobic organisms. If cytochrome c is 0.43% Fe by mass, what is its minimum molecular weight?

Verified step by step guidance

1. Identify the percentage of iron (Fe) in cytochrome c, which is given as 0.43% by mass.
2. Understand that the minimum molecular weight of cytochrome c can be calculated by assuming there is exactly one iron atom per molecule of cytochrome c.
3. Use the atomic mass of iron (Fe), which is approximately 55.85 g/mol, to find the mass of iron in one mole of cytochrome c.
4. Set up the equation: (mass of Fe in one mole of cytochrome c) / (molecular weight of cytochrome c) = 0.0043 (since 0.43% = 0.0043 as a decimal).
5. Solve for the molecular weight of cytochrome c by rearranging the equation: molecular weight of cytochrome c = (mass of Fe in one mole of cytochrome c) / 0.0043.

Key Concepts

Molecular Weight

Molecular weight, or molar mass, is the mass of one mole of a substance, typically expressed in grams per mole (g/mol). It is calculated by summing the atomic weights of all atoms in a molecule. Understanding molecular weight is essential for stoichiometric calculations and determining the composition of compounds.

Mass Percent Composition

Mass percent composition refers to the percentage by mass of each element in a compound. It is calculated by dividing the mass of the element in one mole of the compound by the total mass of the compound, then multiplying by 100. This concept is crucial for determining the amount of a specific element in a compound, such as the iron content in cytochrome c.

Stoichiometry

Stoichiometry is the branch of chemistry that deals with the relationships between the quantities of reactants and products in chemical reactions. It allows chemists to predict the amounts of substances consumed and produced in a reaction. In this context, stoichiometry helps in calculating the minimum molecular weight of cytochrome c based on its mass percent of iron.