Question

C₃H₈  + 5O₂  --> 3CO₂  + 4 H₂O

Using the above reaction, calculate how many grams of H₂O will be made if 195.0 g of O₂ is reacted?

Answer 1

MM(O₂) = 32 g/mol

n(O₂) $= \frac{195}{32}=6.093 \;mol$

According to the reaction:

n(H₂O) $= \frac{4}{5}n(O_2) = \frac{4}{5} \times 6.093 = 4.875 \;mol$

MM(H₂O) = 18 g/mol

m(H₂O) $= 4.875 \times 18 = 87.75 \;g$

Answer: 87.75 g