Molar mass for O2 vs O

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Funmi Baruwa
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Molar mass for O2 vs O

Postby Funmi Baruwa » Mon Oct 05, 2020 2:13 pm

This may be a dumb question but when calculating the molar mass for O2 do we calculate it as 16 g/mol + 16 g/mol? Or is the molecule mass the same as the singular atom mass? I just need a little clarification, thank you!

Alexandra Ahlschlager 1L
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Re: Molar mass for O2 vs O

Postby Alexandra Ahlschlager 1L » Mon Oct 05, 2020 2:16 pm

You're right, the molar mass of the molecule O2 would be 32 because it would be the molar mass of two oxygen atoms. Hope this helps!

Stuti Pradhan 2J
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Re: Molar mass for O2 vs O

Postby Stuti Pradhan 2J » Mon Oct 05, 2020 2:16 pm

The molar mass of O2 would be 32 g/mol because O2 technically has 2 moles of oxygen. Since oxygen itself has a molar mass of 16 g/mol, you would need to double it to get the molar mass of O2.

Hope this helps!

Wil Chai 3D
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Re: Molar mass for O2 vs O

Postby Wil Chai 3D » Mon Oct 05, 2020 2:17 pm

The molar mass of a single O atom is 16 g/mol, so to calculate the molar mass of O2 which is 2 O's you do 16 + 16.

Sabina House 2A
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Re: Molar mass for O2 vs O

Postby Sabina House 2A » Mon Oct 05, 2020 2:18 pm

Because a molecule of O2 has two oxygen atoms instead of just one, the total mass would be 32 g/mol rather than 16 g/mol which is for just one oxygen atom.

Kyla Villarama 1E
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Re: Molar mass for O2 vs O

Postby Kyla Villarama 1E » Mon Oct 05, 2020 2:21 pm

The molar mass of O2 would be 32 (16+16) since you add the molar mass of two O atoms. Also, it's not a dumb question! :)

Chem_Mod
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Re: Molar mass for O2 vs O

Postby Chem_Mod » Mon Oct 05, 2020 2:23 pm

O2 = 32 g/mol
O (single atom) = 16 g/mol (15.9994 to be precise)

You are most likely getting tripped up on the difference between molecular oxygen (O2) versus atomic oxygen (O, element 8). Molecular oxygen (O2) is the form of oxygen that is present in the air and the air you breathe. A single oxygen atom by itself (O) is too reactive to exist in any detectable amounts (same with nitrogen, N, which exists as N2 in our atmosphere).

Nicoli Peiris 1B
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Re: Molar mass for O2 vs O

Postby Nicoli Peiris 1B » Mon Oct 05, 2020 2:48 pm

The molar mass of O2 is 32 g/mol because there are two oxygen atoms in a O2 molecule! So we would do the atomic mass of oxygen times 2!!

BKoh_2E
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Re: Molar mass for O2 vs O

Postby BKoh_2E » Mon Oct 05, 2020 4:23 pm

Oxygen is a diatomic molecule, so when it is by itself as the air we breathe the atomic mass is 32g instead of 16g. The other diatomic molecules you should be aware of are Hydrogen, Nitrogen, Fluorine, Chlorine, Bromine, and Iodine.

Sreeram Kurada 3H
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Re: Molar mass for O2 vs O

Postby Sreeram Kurada 3H » Mon Oct 05, 2020 4:27 pm

Yes since Oxygen is a diatomic molecule. So since there are 2 atomic molecules, the molar mass would be 32g.

Stacey Phan 2I
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Re: Molar mass for O2 vs O

Postby Stacey Phan 2I » Mon Oct 05, 2020 6:03 pm

The molar mass of O is 16 grams, as stated in the periodic table. The molar mass of O2 is 32 grams (16g + 16g).

Funmi Baruwa
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Re: Molar mass for O2 vs O

Postby Funmi Baruwa » Tue Oct 06, 2020 8:39 am

Thank you all so much for clearing that up!


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