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Alexis Webb 2B
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Postby Alexis Webb 2B » Sat Sep 28, 2019 5:32 pm

Hello, in problem G13 in the fundamentals section, I understand where they got the 5.0x 10^-3 moles from, but I need help understanding where they got 1.0x10^-2 mole of N atoms from. Thanks.

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Re: G.13

Postby Chem_Mod » Sat Sep 28, 2019 5:52 pm

Looking at the molecular formula for NH4NO3, there contain 2 nitrogens in the compound. Therefore you would multiply the moles of NH4O3 by 2.

Justin Seok 2A
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Re: G.13

Postby Justin Seok 2A » Sat Sep 28, 2019 5:54 pm

So in the problem, once you figure out how many moles of NH4NO3 are contained in the 100ml solution, which in this case would be 5.0*10^-3, you can figure out how many moles of N there are for each mole of NH4NO3, which would be two. Then, you can multiply 5.0*10^-3 by 2 to figure out the number of moles of N there are in the solution, thus getting the 1.0x10^-2 moles of N in the end.

Hope this helps!

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Re: G.13

Postby GFolk_1D » Sat Sep 28, 2019 5:57 pm

Hi! I was confused about this at first as well but my TA explained that since you are looking for the specific number of moles of nitrogen atoms each plant will receive, you need to relate the final mole amount to the amount of N moles in the original compound. Since the compound NH4NO3 has 2 nitrogen atoms, you would multiply 0.005mol by 2 to equal 0.01 moles. Hope this helps!

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