If 4.70 g of O2 are reacted with an appropriate amount of H2. The mass of H2O produced is 3.67 g. What is the percent yield ? 2 H2 + O2 → 2 H2O

Answer 1

Write the correctly balanced equation for the formation of water from oxygen and hydrogen:

2H₂(g) + O₂(g) ==> 2H₂O ... balanced equation

Assuming that H2 is present in sufficient amount, then we have...

4.70 g O2 x 1 mole O2/32 g = 0.1469 moles O2

Theoretical yield of H2O = 0.1469 moles O2 x 2 moles H2O/mole O2 x 18 g H2O/mol H2O = 5.29 g H2O

Percent yield = actual/theoretical = 3.67 g/5.29 (x100%) = 69.4%