Question

the reaction of 7.10g carbon with excess O2 yields 12.25g of CO2. what is the percent yield of this reaction?

I have tried everything and looked through all of my notes and nothing is working for stiochiometry

Answer 1

Let me write you a process to follow. Copy this. It will work almost all of your stoichiometry problems.
1. Write and balance the equation.
C + O2 ==> CO2

2. Convert what you have into mols.
mols = grams/atomic mass
7.10/12 = about 0.6 but you need a better answer than that estimate.

3. Using the coefficients in the balanced equation, convert mols C to mols of the product (CO2).
0.6 mols C x (1 mol CO2/1 mol C) = 0.6 x 1/1 = 0.6 mols CO2

4. Now convert mols CO2 to grams.
g = mols x molar mass = about 0.6 x 44 = about 26 g. This is the theoretical yield (TY)

5. The actual yield from the problem is 12.25 (AY)
% yield = (AY/TY)*100 = ?
Remember to rework this from the beginning. My numbers are just estimates.

Answer 2

Thanks! this helped so MUCH! :)

Answer 3

The reaction of 7.95 g of carbon with excess O2 yields 12.1 g of CO2. What is the percent yield of this reaction?