Final answer:
The mass of 1.50 x 10⁻² mol molecular oxygen (O₂) is 0.48 grams, calculated by multiplying the given moles by the molar mass of oxygen gas, which is 32.00 g/mol.
Step-by-step explanation:
To calculate the mass in grams of 1.50 x 10⁻² mol molecular oxygen (O₂), you need to use the molar mass of oxygen gas. The molar mass of O₂ is 32.00 g/mol since each oxygen atom (O) has a molar mass of 16.00 g/mol and O₂ consists of two atoms.
Thus, the mass of 1.50 x 10⁻² mol of O₂ is calculated by multiplying the number of moles by the molar mass of O₂:
Mass of O₂ = (1.50 x 10⁻² mol) x (32.00 g/mol)
Mass of O₂ = 0.48 g
Therefore, the mass of molecular oxygen is 0.48 grams.