Calculate the percentage by mass of the indicated element in the following compounds: e. oxygen in the female sex hormone estradiol, C18H24O2

Verified step by step guidance

1. Step 1: Determine the molar mass of the compound. The molar mass of estradiol, C18H24O2, can be calculated by adding up the molar masses of all the atoms in the compound. The molar mass of carbon (C) is approximately 12.01 g/mol, hydrogen (H) is approximately 1.01 g/mol, and oxygen (O) is approximately 16.00 g/mol.
2. Step 2: Calculate the total molar mass of oxygen in the compound. Since there are two oxygen atoms in the compound, multiply the molar mass of oxygen by 2.
3. Step 3: Calculate the percentage by mass of oxygen in the compound. This can be done by dividing the total molar mass of oxygen by the molar mass of the compound, and then multiplying the result by 100 to get the percentage.
4. Step 4: The result from step 3 is the percentage by mass of oxygen in estradiol.

Key Concepts

Molar Mass

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 masses of all the atoms in a chemical formula. For estradiol (C18H24O2), the molar mass is determined by adding the contributions from carbon, hydrogen, and oxygen atoms, which is essential for calculating the percentage by mass of any specific element.

Percentage by Mass

Percentage by mass is a way to express the concentration of an element within a compound. It is calculated using the formula: (mass of the element in the compound / total mass of the compound) × 100%. This concept is crucial for determining how much of a specific element, such as oxygen in estradiol, contributes to the overall mass of the compound.

Chemical Formula Interpretation

Interpreting a chemical formula involves understanding the composition of a compound based on the symbols and subscripts used. In the formula C18H24O2 for estradiol, the subscripts indicate the number of each type of atom present. This understanding is vital for accurately calculating the total mass of the compound and the mass of the specific element of interest, which is necessary for the percentage by mass calculation.