Answer:
amount of H₂O = 6.825 g
Explanation:
Data Given:
mass of C₆H₆O₃ = 40.8 g
percent yield = 39.0 %
amount of H₂O = ?
Solution:
First we have to write the complete reaction
C₆H₆O₃ + 6 O₂ ----------> 6 CO₂ + 3 H₂O
So, if we look at the reaction
C₆H₆O₃ + 6 O₂ ----------> 6 CO₂ + 3 H₂O
1 mol 3 mol
From the above reaction we come to know that C₆H₆O₃ and H₂O are in 1 : 3 mole ration that is one mole of C₆H₆O₃ produce 3 moles of H₂O
As the percent yield is 39% so it means that all the C₆H₆O₃ has not used in the reaction and Oxygen is limiting reagent.
To Know the Theoretical yield of H₂O we have to convert moles to mass
molar mass of C₆H₆O₃ = 126 g/mol
molar mass of H₂O = 18 g/mol
Now
C₆H₆O₃ + 6 O₂ ----------> 6 CO₂ + 3 H₂O
1 mol (126 g/mol) 3 mol (18 g/mol)
126 g 54 g
Now come to know that if 126 g of C₆H₆O₃ produce 54 g of H₂O then wat mass of water will be produce by 40.8 g of C₆H₆O₃.
apply unity formula
126 g of C₆H₆O₃ ≅ 54 g of H₂O
40.8 g of C₆H₆O₃ ≅ X g of H₂O
By cross multiplication:
mass of H₂O = 40.8 g x 54 g / 126 g
mass of H₂O = 17.5 g
To find the actual mass of H₂O
formula will be used
percent yield of H₂O = actual yield / theoretical yield x 100
Rearrange the above formula
actual yield = (percent yield of H₂O / theoretical yield)/100 . . . . . (1)
Put values in equation 1
actual yield of H₂O = (39 x 17.5 g ) x 100
actual yield H₂O = (682.5 g ) x 100
actual yield H₂O = 6.825 g
So Amount of H₂O produce = 6.825 g