Answer:
C. 0.1 mol of V₂O₅
Explanation:
Number of moles of oxygen atoms present in each molecule is derived as follows:
A. Number of molecules of CO₂ in 12.044 * 10²³ molecules of CO₂ = 12.044 * 10²³/6.022 * 10²³ = 2 moles of CO₂ molecules
Each molecule of CO₂ contains 2 atoms of oxygen. Therefore, number of moles of oxygen atom present in 2 molecules of CO₂ = 2 * 2 moles of oxygen atoms = 4 moles of oxygen atoms.
B. Number of moles of O₃ molecules in 12g of O₃ = mass of O₃/molar mass of O₃
molar mass of O₃ = 48 g/mol
Number of moles of O₃ molecules = 12/48 = 0.25 moles of O₃
There are 3 atoms of oxygen in a molecule of O₃, therefore number of moles of oxygen atoms present in 12 g of O₃ = 3 * 0.25 = 0.75 moles of oxygen atoms
C. There are 5 oxygen atoms in a molecule of V₂O₅
0.1 mol of V₂O₅ contains 0.1 * 5 moles of oxygen atoms = 0.5 moles of oxygen atoms.
D. mass of 10 mL of H₂O = 10 g since the density of H₂O = 1 g/mL
molar mass of H₂O = 18.0 g/mol
Number of moles of H₂O in 10 g of H₂O = 10/18 = 0.56 moles
There are 1 atom of oxygen in a molecule of H₂O, therefore, number of moles of oxygen present in 10 g of H₂O = 0.56 * 1 = 0.56 moles of oxygen atoms
Therefore, 0.1 mole of V₂O₅ contains the least number of oxygen atoms.
