Final answer:
The molecular mass of the aspirin molecule (C9H8O4) is calculated at 180.15 amu. Percent composition of each element is found by dividing the total mass of the element in a mole of aspirin by the molar mass of aspirin and multiplying by 100. This is essential for pharmaceutical preparations and chemical reaction analysis.
Step-by-step explanation:
The compound found in aspirin, which has a molecular formula of C9H8O4, has a molecular mass of 180.15 atomic mass units (amu). This mass is determined by adding together the atomic masses of nine carbon atoms, eight hydrogen atoms, and four oxygen atoms. In order to calculate the percent composition of each element within aspirin, one would take the total mass of each element in a mole of aspirin and divide it by the molar mass of aspirin, then multiply by 100 to get a percentage.
For example, the molar mass of carbon in aspirin is the atomic mass of carbon (approximately 12.01 amu) multiplied by the number of carbon atoms (9), which would then be divided by the molar mass of aspirin (180.15 amu) and multiplied by 100 to find its percent composition. Similar calculations would be carried out for hydrogen and oxygen. This concept is crucial not only for understanding the composition of aspirin but also for the preparation of pharmaceuticals and analysis of chemical reactions involving aspirin.