If 100 g of H2O is produced from 16 g of H2, What is the % yield of H2O?

Question

(Molar mass: H= 1g/mol; O=16 g/mol)

H2 + O2 → 2H2O

Answer 1

First, let's calculate how many moles of H2 were used:

16 g H2 / 2 g/mol = 8 mol H2

According to the balanced equation, 1 mol of H2 produces 2 mol of H2O. Therefore, the theoretical yield of H2O can be calculated as:

8 mol H2 x 2 mol H2O/mol H2 = 16 mol H2O

Now, let's calculate the actual yield. We were given that 100 g of H2O was produced, which can be converted to moles:

100 g H2O / 18 g/mol = 5.56 mol H2O

The percent yield can then be calculated as:

(actual yield / theoretical yield) x 100%

= (5.56 mol H2O / 16 mol H2O) x 100%

= 34.8%

Therefore, the percent yield of H2O is 34.8%. This indicates that the reaction did not produce as much H2O as would be expected from the amount of H2 used, and some H2 may have been lost or reacted in other ways.