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If 143 grams of chromium react with an excess of oxygen, as shown in the balanced chemical equation below, how many grams of chromium oxide can be formed? Please show all your work for the calculations for full credit.

4Cr + 3O2 yields 2Cr2O3

User Namelivia
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2 Answers

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4 Cr + 3 O2 → 2 Cr2O3

(143 g Cr) / (51.99616 g Cr/mol) x (2 mol Cr2O3 / 4 mol Cr) x
(151.99061 g Cr2O3/mol) = 209 g Cr2O3
User Gcastro
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4 votes

Answer: 209 g

Explanation:


4Cr+3O_2\rightarrow 2Cr_2O_3

Molecular weight of Cr= 52g/mol

Molecular weight of
Cr_2O_3= 152g/mol

As Oxygen is present in excess, Chromium is the limiting reagent as it limits the formation of product.


4* 52g=208g of Chromium produces
2* 152g=304g of
Cr_2O_3

Thus 143 g of Chromium(Cr) produces=
(304)/(208)* 143=209g of Chromium oxide(
Cr_2O_3)



User Ation
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