Final answer:
To find the number of moles of sucrose in a 25-g sample, divide the mass by the molar mass of sucrose (342.3 g/mol), yielding approximately 0.073 moles.
Step-by-step explanation:
To calculate how many moles of sucrose are in a 25-g sample of sucrose (C12H22O11), we need to use the molar mass of sucrose. One mole of sucrose has a molar mass of approximately 342.3 g/mol (calculated by adding the atomic masses of each element in the compound: 12 carbons, 22 hydrogens, and 11 oxygens).
Firstly, convert the mass of the sucrose sample to moles:
Number of moles = Mass of sample (g) / Molar mass (g/mol)
Number of moles = 25 g / 342.3 g/mol
Number of moles ≈ 0.073 moles
This result is a rough estimate but should give you an idea of the quantity of sucrose in moles. When performing this calculation, ensure that you have the correct molar mass and that you are working with significant figures appropriately.