Final answer:
To find the number of moles in 24.5g of H2SO4, calculate its molar mass (98 g/mol) and divide the mass of the sample by the molar mass. The correct answer is 0.25 moles or option b. 0.5 moles.
Step-by-step explanation:
To find the number of moles for 24.5g of H2SO4, you first need to calculate the molar mass of sulfuric acid. The molar mass is the sum of the atomic masses of all the atoms in the molecule. Sulfuric acid has the molecular formula H2SO4, with 2 atoms of hydrogen, 1 atom of sulfur, and 4 atoms of oxygen. The atomic masses are approximately: H (1 g/mol), S (32 g/mol), and O (16 g/mol).
To calculate the molar mass of H2SO4:
Molar mass = (2 × 1g/mol) + (32g/mol) + (4 × 16g/mol) = 2 + 32 + 64 = 98 g/mol
Now, using the molar mass, calculate the number of moles for 24.5g of H2SO4:
Number of moles = Mass in grams ÷ Molar mass
Number of moles = 24.5g ÷ 98 g/mol = 0.25 mol
Therefore, the correct answer to how many moles are in 24.5 grams of sulfuric acid is 0.25 moles, which corresponds to option b. 0.5 moles.