To find the number of moles of carbon dioxide that contains 8 grams of oxygen, we first need to determine the molar mass of oxygen and carbon dioxide.
The molar mass of oxygen (O) is 16 g/mol.
The molar mass of carbon dioxide (CO2) is calculated by adding the molar masses of carbon (C) and two oxygen atoms (O). The molar mass of carbon is 12 g/mol, and since there are two oxygen atoms in carbon dioxide, we multiply the molar mass of oxygen by 2. Therefore, the molar mass of carbon dioxide is:
Molar mass of carbon dioxide (CO2) = (12 g/mol) + 2(16 g/mol) = 44 g/mol
Now, we can use the molar mass of oxygen to find the number of moles of oxygen in 8 grams:
Number of moles of oxygen = (mass of oxygen) / (molar mass of oxygen)
= 8 g / 16 g/mol
= 0.5 mol
Since there are two oxygen atoms in one molecule of carbon dioxide, the number of moles of carbon dioxide will be half of the number of moles of oxygen:
Number of moles of carbon dioxide = (number of moles of oxygen) / 2
= 0.5 mol / 2
= 0.25 mol
Therefore, the correct answer is D) 0.25 mole.