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Help with my workings.

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Hey, Ive been given a question and I was a bit unsure on my workings or answer could somebody clarify what I've done please.

 

Hydrogen peroxide is a very useful and environmentally friendly bleaching agent. It can be

 

produced in a controlled (slow) way by the reaction.

 

CaO2(s) + 2 H2O(l) Ca(OH)2(s) + H2O2(aq)

 

How many grams of H2O2 would be produced if 20.0 g of CaO2 were reacted with 15.0 g of

 

H2O?

 

(Molar masses in g/mol are: CaO2 = 72.0; H2O = 18.0; Ca(OH)2 = 74.0 and H2O2 = 34.0)

 

 

 

 

 

Step 1:

 

n(CaO2) = (1mol CaO2)x(20.0g CaO2)/(72.08g CaO2)= 0.2774694 mol CaO2

 

n(H2O) = (1mol H2O)x(15.0g H2O)/(18.016g H2O)= 0.8325932 mol H2O

 

 

 

Step 2:

 

0.2774694 mol CaO2 x 2 mol H2O/ 1 Mol CaO2 = 0.5549388 Mol H2O

 

H2O is limiting

 

 

 

Step 3:

 

0.8325932 mol H2O x 1 mol H2O2/ 2 mol CaO2 = 0.416296 mol H2O2

 

 

 

Step 4:

 

0.416296 mol H2O2 x 34.016g H2O2/1 mol H2O2 = 14.2g H2O2 is produced

 

 

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