The percent yield of
To determine percent yield, you will need both the actual yield and the theoretical yield. The actual yield is the yield from carrying out the experiment, given in the question. However, you will have to mathematically/stoichiometrically calculate the theoretical yield.
In the question, you are told that the reaction produces 6.81 g of CaO. This is your actual yield.
Now you need the theoretical yield. To do this you will have to perform unit conversion/dimensional analysis using the balanced chemical equation.
For the purposes of a balanced equation (and communication of the general method for these questions), I'll just use:
Now, you know you start with 20.7 g of
If we use the molar mass of
Now that you have moles of
Now that the moles of
Now, you are looking for grams of
Now, if you've done everything correctly, all the units should cancel out, leaving you with grams of
Now to calculate the percentage yield the expression is:
% yield = (actual yield / theoretical yield) * 100%
Substituting the information we have we get:
Hopefully, although long, everything was clear and explained in enough detail! If you have any questions, let me know! :)