Question

An aspirin tablet contains 75.0 mg of aspirin, which has the molecular formula, c9h8o4.

Answer 1

An aspirin molecule with the formula C9H8O4 has a molecular mass of 180.15 amu. The number of moles in 2.50 g of aspirin is calculated using the mass and molar mass, which aids in understanding dosage and percent composition.

Step-by-step explanation:

The molecular mass of an aspirin molecule, which has the molecular formula C9H8O4, is calculated by adding the atomic masses of its constituent atoms. As specified, this value amounts to 180.15 amu. To calculate the number of moles present in a given mass of aspirin, such as 2.50 g, we use the formula:

number of moles = mass (g) / molar mass (g/mol)

Therefore, for aspirin:

number of moles = 2.50 g / 180.15 g/mol

After calculating, we find that the number of moles of aspirin in 2.50 g is approximately 0.01387 moles. Knowing the molecular mass and using the concept of moles allows us to understand the percent composition, determine the number of molecules in a given mass, and relate these ideas to real-world applications such as the dosage of medicines like aspirin and acetaminophen.

Answer 2

You can find 1) how many moles of aspirin are in the tablet, and 2) how many molecules of aspirin are in the tablet

1) Formula: number of moles = mass in grams / molar mass

Molar mass of C9H8O4:

9*12.0g/mol + 8*1.0 g/mol + 4*16.0g/mol = 180 g/mol

mass of aspirin = 75.0 mg = 0,075 g

=> number of moles of aspirin = 0,075 g / 180 g/mol = 0.0004167 moles

=> Answer 1) 0.000417 moles of aspirin


2) number of molecules = number of moles * Avogadro's number =>

number of molecules = 0,000417 moles * 6.022 * 10^23 molecules / moles =

= 2.51 * 10^20 molecules.

Answer 2: 2.51 * 10^20 molecules