Answer:
4.92×10²³ atoms of oxygen.
Step-by-step explanation:
We'll begin by calculating the number of mole of oxygen in 1 mole of CO₂. This can be obtained as follow:
1 mole of CO₂ contains 2 mole of oxygen.
1 mole of CO₂ = 12 + (2×16)
= 12 + 32
= 44 g
Thus,
44 g of CO₂ contains 2 moles of oxygen.
Next, we shall determine the number of mole of oxygen in 18 g of CO₂. This can be obtained as follow:
44 g of CO₂ contains 2 moles of oxygen.
Therefore, 18 g of CO₂ will contain
= (18 × 2)/ 44 = 0.818 mole of oxygen.
Finally, we shall determine the number of atoms in 0.818 mole of oxygen. This can be obtained as follow:
From Avogadro's hypothesis,
1 mole = 6.02×10²³ atoms.
Therefore,
0.818 mole = 0.818 × 6.02×10²³ atoms.
0.818 mole of oxygen = 4.92×10²³ atoms.
Thus, 18 g of CO₂ contains 4.92×10²³ atoms of oxygen.