1. How many oxygen atoms are in 96.1 g of CO₂?
To solve this problem we will have to do multiple conversions. First we will convert those grams into moles of molecules of CO₂. Then we will find the number of molecules of CO₂. And finally we will convert molecules of CO₂ to atoms of O.
We need the atomic mass of O and C to find the molar mass.
atomic mass of O = 16.00 amu atomic mass of C = 12.01
molar mass of CO₂ = 1 * 12.01 + 2 * 16.00
molar mass of CO₂ = 44.01 g/mol
Once that we know the molar mass of CO₂ we can find the number of moles of CO₂ that we have in 96.1 g of it.
number of moles of CO₂ = mass of CO₂/(molar mass of CO₂)
number of moles of CO₂ = 96.1 g/(44.01 g/mol)
number of moles of CO₂ = 2.18 moles
Using Avogadro's number we can find the number of molecules of CO₂ that we have in 2.18 moles of it.
1 mol of molecules of CO₂ = 6.022 * 10^23 molecules of CO₂
number of CO₂ molecules = 2.18 moles of molecules of CO₂ * 6.022 * 10^23 molecules of CO₂/( 1 mol of molecules of CO₂)
number of CO₂ molecules = 1.31 * 10^24 molecules
Since there are 2 atoms of O in 1 molecule of CO₂, we can calculate the number of O atoms that we have in 1.31 * 10^24 molecules of CO₂.
1 molecule of CO₂ = 2 atoms of O
number of O atoms = 1.31 * 10^24 molecules of CO₂ * 2 atoms of O/1 molecule of CO₂
number of O atoms = 2.62 * 10^24 atoms of O
Answer: there are 2.62 * 10^24 atoms of O in 96.1 g of CO₂.