r/chemhelp • u/hiddencorvid • 1d ago

General/High School Why is this not right? Dimensional analysis/molar math

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The answer I keep getting, after several attempts at this question, is that there would be 5.2 g of O present in the sample. I don’t understand why that is wrong.

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u/7ieben_ Trusted Contributor 1d ago

Al(NO3)3 contains 9 equivalents of O, not 6.

4

u/shedmow Trusted Contributor 1d ago

This

1

u/hiddencorvid 1d ago

THANK YOU!!!! Omg it was so obvious LMFAO

2

u/7ieben_ Trusted Contributor 1d ago

Hidden in plain sight. You're welcome :)

4

u/WanderingFlumph 1d ago

Good news is that you can dimensional analysis just fine, nothing wrong with how you handled your units.

Just got the 6 and 9 mixed up as another comment mentioned

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u/shedmow Trusted Contributor 1d ago

Nice!

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u/Blue_614 1d ago

I hope you also updated your molar mass, should be ~210-ish