Question

Gaseous hydrogen can be used as a clean fuel since it only produces water according to the following fuel reaction:

H2 (g) + O2 (g) = H2O (g)

If this reaction has a 98% experimental yield, determine the necessary mass of H2 to produce 1000.0 kg of water.

Answer 1

Suppose we need X kg of H₂ to produce 1000 Kg of water.

moles of H₂ in X kg mass

reaction H₂(g) + O₂(g)    H₂O(g)

thoeretically according to reaction, one mol H₂ produce , one mole of water..

so 500X mol H₂ will produce 500X mol of water theoretically ( it's called thoeretical yield).

moles of water in 1000 kg = 1000,000 gm

moles of water = 1000,000 / 18 = 55555.56 mol

but actually we need 1000 Kg water ( 55555.56 mol water) this is actual yield.

percentage yield is given by

  

reaction have 98% yield.