how many molecules are in 5.5 moles of oxygen gas? How many atoms are in this quantity of gas?
I used dimensional analysis and did:
5.5 mol. of oxygen x 6.02x10^23 molecules/1 mol of oxygen
I got 3.3x^24 molecules of oxygen
How do I find the # of atoms? I know that there are 2 atoms of oxygen in one molecule of oxygen gas, so do I divide my answer by 2 to get the # of atoms?
Right on all except what you do for atoms. You are right that each molecule oxygen contains two atoms of O so doesn't it stand to reason that O atoms will be twice O molecules.
that makes sense, thank you!
To find the number of atoms in the given quantity of oxygen gas, you are correct to consider that there are 2 atoms of oxygen in one molecule of oxygen gas (O2). However, you don't need to divide the number of molecules by 2, but rather multiply it by 2. Here's how you can calculate it:
You already calculated that there are 3.3x10^24 molecules of oxygen. Now, to find the number of atoms, you can use the following conversion factor:
1 molecule of oxygen gas (O2) = 2 atoms of oxygen (O)
Therefore, you can multiply the number of molecules by the conversion factor:
3.3x10^24 molecules x (2 atoms/1 molecule)
You can simplify this expression by canceling out the units "molecules" and performing the multiplication:
3.3x10^24 x 2 = 6.6x10^24
So, there are approximately 6.6x10^24 atoms in 5.5 moles of oxygen gas.