Question

How many oxygen atoms are there in 0.0011 g of carbon dioxide? (l = 6.02 × 10²³, ar values: C = 12.0, O = 16.0)

Options:
Option 1: 1.25 × 10²² atoms
Option 2: 3.01 × 10²² atoms
Option 3: 6.02 × 10²² atoms
Option 4: 1.20 × 10²³ atoms

Answer 1

To find the number of oxygen atoms in 0.0011 g of CO₂, calculate the moles of CO₂ then multiply it by 2 for the oxygen atoms and finally by Avogadro's number. The result is 3.01 x 10²² oxygen atoms.

Step-by-step explanation:

To calculate the number of oxygen atoms in 0.0011 g of carbon dioxide (CO₂), we first need to determine the number of moles of CO₂ that corresponds to 0.0011 grams. Using the molar mass of CO₂, which is 44.009 g/mol (1x12.011 g C.mol⁻¹ + 2x15.999 g O.mol⁻¹), we can calculate the number of moles of CO₂ in 0.0011 grams.

Number of moles of CO₂ = 0.0011 g / 44.009 g/mol = 2.4996 x 10⁻⁵ moles

Since one mole of CO₂ contains two moles of oxygen atoms, we then multiply the number of moles of CO₂ by 2 to get the moles of oxygen atoms.

Moles of oxygen atoms = 2.4996 x 10⁻⁵ moles CO₂ x 2 = 4.9992 x 10⁻⁵ moles O

Finally, we use Avogadro's number to convert moles of oxygen atoms to the number of oxygen atoms.

Number of oxygen atoms = 4.9992 x 10⁻⁵ moles O x 6.022 x 10²³ atoms/mole = 3.01 x 10²² atoms

Therefore, there are 3.01 x 10²² oxygen atoms in 0.0011 g of carbon dioxide, which corresponds to Option 2.