Question

18.6g of hydrogen reacts with excess of nitrogen and if the actual yield is 15.2g what is the percent yield

Answer 1

the reaction is given by

3H2 + N2 ---> 2NH3

we know that

moles = mass / molar mass

so

moles of H2 = 18.6 / 2

moles of H2 = 9.3

now

consider the reaction

3H2 + N2 ---> 2 NH3

we can see that

moles of NH3= ( 2/3 ) x moles of H2

so

theoretical moles of NH3 = (2/3) x 9.3

theoretical moles of NH3 = 6.2

now

mass = moles x molar mass

so

theoreatical mass of NH3 produced = 6.2 x 17

theoretical mass of NH3 produced = 105.4

now

we know that

percent yield = ( acutal / theoretical) x 100

so

percent yield = ( 15.2 / 105.4) x100

percent yield = 14.42

so

the percent yield is 14.42