Question

Use the equation below to solve the problem that follows.

2H2 (g) + O2 (g) → 2H2O (g)

When David reacts 13.8 grams of hydrogen gas with excess oxygen, 87.0 grams of water are formed. Calculate his percent yield of water.

Answer 1

Percent yield = 70%

Further eplanation

Percent yield is the comparison of the amount of product obtained from a reaction with the amount you calculated

General formula:

Percent yield = (Actual yield / theoretical yield )x 100%

An actual yield is the amount of product actually produced by the reaction. A theoretical yield is the amount of product that you calculate from the reaction equation according to the product and reactant coefficients

Reaction

2H₂ (g) + O₂ (g) → 2H₂O (g)

• mass of H₂O (theoretical) :

`\tt mass=mol* MW(mol~ratio~H_2O/ H_2=2/ 2)\\\\mass=((2)/(2)* (13.8)/(2))* 18~g/mol\\\\mass=124.2~g`

• percent yield

`\tt \%yield=(87)/(124.2)* 100\%=\boxed{\bold{70\%}}`