help pleae. How many moles of oxygen are formed when 58.6 g of KNO3 decomposes according to the following reaction? The molar mass of KNO3 is 101.11 g/mol.

4 KNO3(s) → 2 K2O(s) + 2 N2(g) + 5 O2(g)

Question

help pleae. How many moles of oxygen are formed when 58.6 g of KNO3 decomposes according to the following reaction? The molar mass of KNO3 is 101.11 g/mol.

4 KNO3(s) → 2 K2O(s) + 2 N2(g) + 5 O2(g)

thomaster · Answer

the rate is 4:5
4 mol KNO3 is used to produce 5 mol oxygen

first calculate how many moles of KNO3 you have.
Use this:

thomaster · Answer

with rate, I meant ratio

anonymous · Answer

thank you

thomaster · Answer

Well we're not done yet :P
First convert grams to mole. then calculate how many moles of oxygen are produced by using the ratio.

anonymous · Answer

okay and whats next?

thomaster · Answer

that's it...
Did you convert grams to moles?

anonymous · Answer

yes and then I converted my answer back to grams using the ratio.

thomaster · Answer

you don't have to convert it back to grams..
can you show me your work?

anonymous · Answer

okay yes of course.

anonymous · Answer

5.6gKNO3*1mole/101.11gKNO3*5/2=0.13 is that correct?

thomaster · Answer

you only have to divide grams by the molar mass.

$\large\sf\dfrac{58.6\ g}{101.11}=0.58\ mol$

anonymous · Answer

and then I multiply 0.58mol times the ratio?

thomaster · Answer

then you use a cross table to calculate the mol O2 produced.
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