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Topic: Probably pretty simple question from basics of chemical calculations.  (Read 1493 times)

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Offline Borek

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Re: Probably pretty simple question from basics of chemical calculations.
« Reply #15 on: June 26, 2024, 05:13:31 PM »
"Mixture of NaNO3 and Na2SO4 weights 5.37g and contains 1.61g of sodium. What is the mass percentage of NaNO3 in this mixture?"

Check that the given answer (45%) doesn't give 1.61 g of Na.
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Offline windom626

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Re: Probably pretty simple question from basics of chemical calculations.
« Reply #16 on: June 26, 2024, 05:14:25 PM »
To  Hunter2:
So as I have written:

N1*85+N2*142=5.37
N1*62+N2*96=3.76

Yes? Well we get
N1= 0.028 mole of NaNO3
N2= 0.020 mole of Na2SO4

This means - 0.028*85 = 2.38g of NaNO3
and 2.84 g of Na2SO4

This means

2.38 / 5.37 *100% = 44.3%

Which for me is now just a rounding up issue - and it's a correct answer.
Yes?

Offline Borek

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Re: Probably pretty simple question from basics of chemical calculations.
« Reply #17 on: June 26, 2024, 05:19:28 PM »
N1*85+N2*142=5.37

Try with a correct value of 5.71
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Offline Borek

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Re: Probably pretty simple question from basics of chemical calculations.
« Reply #18 on: June 26, 2024, 05:19:42 PM »
Why not follow what I wrote.

Because it is an unnecessary detour that in no way makes solving the problem easier nor simpler?
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Offline windom626

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Re: Probably pretty simple question from basics of chemical calculations.
« Reply #19 on: June 26, 2024, 06:31:41 PM »
Case closed. Both ways were correct. Thanks for answers. Forever I will remember this.

Did the next excercise, same idea, diffrent compounds I got it right in first aproach.

Thanks!

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