Factor(s) that affect percent yield

[soggybread]

Hi everyone,
For a science lab, I am asked to find the following:

What factor(s) affect percent yield in a reaction which produces calcium carbonate?

We are given a selection of chemicals to use to get the CaCl_2 but I have chosen the following:

CaCl_2 + Na_2CO_3 --> CaCO_3 + 2NaCl

We are to do at least 4 trials of changing the grams of Na_2CO_3.
I'm not sure what are the factors that affect % yeild. Would is be Molarity?
Any help would be appreciated,
Chris.

 

[soggybread]

anyone? :/

 

[Plastic Photon]

% yield has two factors, theoretical and actual yield. There should be nothing that varies with your theoretical yield, so it should be your actual yield in the 4 trials that affect your % yield.

EDIT: wait, as long as you 'do not' change the quantity of chemical in your trials, the theoretical yield should not change. But it will vary if you do change the quantities.