Question

Disulfur dichloride is produced by reacting chlorine gas with molten sulfur.
S8 + 4 Cl2 --> 4 S2Cl2
What is the percent yield if 6.25 g S2Cl2 is isolated from the reaction of 10.0 g S8 and 7.50 g Cl2?

Answer 1

Find your limiting reagent first. Determine the number of moles of each reactant and work out which is in excess based on the stoichiometric rations in the balanced equation.
Once you know the limiting reagent, work with the stoichiometry again to determine the number of moles of product expected. Then find the mass of this expected (theoretical) yield.
Finally, percent yield is found using:
\[\% ~\text{yield} = \frac{\mid \text{expected yield} - \text{actual yield} \mid}{\text{expected yield}} \times 100\]

Hope this helps ...