Question

Determine the number of atoms of O in 10.0 g of CO2.

Answer 1

To calculate the number of atoms of O in 10.0 g of CO2, first convert the mass of CO2 to moles, then use the mole ratio to find moles of O, and finally multiply by Avogadro's number to obtain the total number of atoms of O.

Step-by-step explanation:

To determine the number of atoms of O in 10.0 g of CO2, we first need to find the number of moles of CO2 because the number of moles will tell us how many molecules of CO2 we have, and thus how many atoms of O we have.

Step 1: Calculate the number of moles of CO2 in 10.0 g.

• The molar mass of CO2 = 44.01 g/mol (12.01 g/mol for C + 2 × 16.00 g/mol for O).
• Number of moles of CO2 = Mass of CO2 / Molar mass of CO2
• Number of moles of CO2 = 10.0 g / 44.01 g/mol = 0.227 mol.

Step 2: Calculate the number of atoms of O in the moles of CO2.

• One mole of CO2 contains 2 moles of O atoms.
• Number of moles of O = 2 × Number of moles of CO2 = 2 × 0.227 mol.
• Number of moles of O = 0.454 mol.

Step 3: Calculate the number of atoms of O.

• In one mole, there are Avogadro's number of atoms, which is approximately 6.022 × 10²³ atoms/mol.
• Number of atoms of O = Number of moles of O × Avogadro's number.
• Number of atoms of O = 0.454 mol × 6.022 × 10²³ atoms/mol.
• Number of atoms of O = 2.734 × 10²³ atoms.

Therefore, there are approximately 2.734 × 10²³ atoms of O in 10.0 g of CO2.

Answer 2

1.37 × 10²³ atoms CO₂

Step-by-step explanation:

Step 1: Define

Avagadro's Number: 6.02 × 10²³ atoms, molecules, formula units

Molar Mass C - 12.01 g/mol

Molar Mass O - 16.00 g/mol

Molar Mass CO₂ - 44.01 g/mol

Step 2: Use Dimensional Analysis

`10.0 \hspace{3} g \hspace{3} CO_2(\frac{1 \hspace{3} mol \hspace{3} CO_2}{44.01 \hspace{3} g \hspace{3} CO_2} )(\frac{6.02(10)^(23) \hspace{3} atoms \hspace{3} CO_2}{1 \hspace{3} mol \hspace{3} CO_2} )` = 1.36787 × 10²³ atoms CO₂

Step 3: Simplify

We have 3 sig figs.

1.36787 × 10²³ atoms CO₂ ≈ 1.37 × 10²³ atoms CO₂