Calculate the mass percent composition of each element in each compound. (a) \(\mathrm{FeCl}_{3}\) (b) \(\mathrm{TiO}_{2}\) (c) \(\mathrm{H}_{3} \mathrm{PO}_{4}\) (d) \(\mathrm{HNO}_{3}\)

Understanding the molar mass of a compound is crucial for a plethora of chemical calculations, from reacting quantities to concentration and beyond. To calculate the molar mass, one must first look up the atomic masses of each element in the compound from the periodic table. The atomic mass is the weight of a single mole of an element and is measured in grams per mole (g/mol).

Then, these values are combined according to the compound's chemical formula. For example, for water (H₂O), you would take the atomic mass of Hydrogen (approximately 1.01 g/mol), multiply it by two for the two Hydrogen atoms, and then add the atomic mass of Oxygen (approximately 16.00 g/mol).

One common mistake is to overlook that the subscript in the chemical formula indicates the number of atoms in that compound. Always multiply the atomic mass of each element by the number of atoms of that element present in the compound before summing them up.

Percent composition by mass shows the proportion each element contributes to the total mass of the compound. It is a fundamental concept for those studying stoichiometry and other areas of chemistry. After calculating the molar mass of the compound, determine the mass percent for each individual element by dividing the total atomic mass of that element (as represented in one mole of the compound) by the molar mass of the compound, then multiply the result by 100%.

For instance, in methane (CH₄), Carbon's mass percent is calculated by dividing the atomic mass of a single Carbon atom by the molar mass of methane and multiplying by 100%. The same process is then repeated for Hydrogen. These calculations are fundamental in finding out the empirical and molecular formulas of unknown compounds based on their mass percent composition.

Chemical compound analysis involves determining the composition and proportions of a chemical compound. Methods range from simple, like the percent composition calculations discussed earlier, to advanced instrumental techniques like mass spectrometry and nuclear magnetic resonance (NMR).

In academic settings, learning to calculate the mass percent composition of each element lays the groundwork for more complex analyses. This essential skill aids in predicting the physical properties and chemical behavior of substances. Moreover, an accurate analysis affects the outcome of chemical reactions, product purity in pharmaceuticals, and the suitability of materials for specific applications in industry.