J.R. S. answered 12/10/19
Ph.D. University Professor with 10+ years Tutoring Experience
To find % yield, we need to know the actual yield and the theoretical yield. Then, the percent yield is the actual yield / theoretical yield (x100%).
We are given the actual yield, which is stated to be 12.4 g SOCl2. So, let us find the theoretical yield, i.e. the yield if you got 100% conversion to product.
Theoretical yield:
Reaction is SO2 + 2Cl2 ==> SOCl2 + Cl2O (assuming this is the reaction you refer to)
6.11 g SO2 x 1 mol SO2/64.1 g x 1 mol SOCl2 / mol SO2 x 119 g/mol SOCl2 = 11.34 g SOCl2 theoretical yield
percent yield = actual/theoretical (x100) = 12.4 g/11.34 g (x100) = 109% (impossible to have >100%)
(NOTE THAT THE ACTUAL YIELD IS GREATER THAN THEORETICAL. IMPOSSIBLE)
So, the only conclusion is that there is an error in the question of the reaction was meant to be
SO2 + Cl2 ==> SO2Cl2 and they meant to ask for the percent yield of SO2Cl2 instead of SOCl2.