Stoichiometry of a Precipitation Reaction|

.6Name: Danielle Hall|Date: 10.15.2012|
Exp 9: Stoichiometry of a Precipitation Reaction|Lab Section: |

Data Tables:

Step 3: Show the calculation of the needed amount of Na2CO3
CaCl2.H2O(aq)= m/M
=1/147
=0.0068 mol
CaCO3(s)=0.0068*1/1
=0.0068 mol
CaCO3(s)=
CaCO3 (s)= CaCO3 mol *CaCO3 g
=0.0068 mol*100.01 g
=.68 g
Step 4:

Mass of weighing dish _0.6___g
Mass of weighing dish and Na2CO3 __0.72__g
Net mass of the Na2CO3 ___0.12_g Step 6:

Mass of filter paper __1.0__g

Step 10:

Mass of filter paper and dry calcium carbonate __1.7__g
Net mass of the dry calcium carbonate ___0.7_g (This is the actual yield) Step 11: Show the calculation of the theoretical yield of calcium carbonate.
.0068 mol of CaCO3 *100.06 g CaCO3/1mol of CaCO3
=.6804 g of CaCO3

Show the calculation of the percent yield.

(Actual yield/theoretical yield)*100
= (.7/.68)*100
=102%

Conclusion:
The objectives of this experiment were to use stoichiometry as a method to predict the amount of product produced from a precipitation reaction, to measure the reactants and products of the reaction with accuracy, and to discover the percent yield by calculating the actual yield and the theoretical yield
The mass of the weighing dish was measured as 0.6 g. The mass of the filter paper was measured as 1.0 g. Initially it was calculated that 0.68 g of CaCO3 was needed for a full reaction. The net mass of Na2CO3 (reactant) was 0.72 g and the net mass of CaCO3 was 0.7 g. The dried calcium carbonate measured at 0.7 g (net mass).
The purpose of this experiment is to demonstrate a precipitation reaction combined with stoichiometry. The experiment also provided a method to improve substance measurement with utilizing measuring tools e.g. digital scales, beakers, and cylinders. A Precipitation reaction begins by combining two aqueous solutions to form a precipitate, an insoluble product that is also a solid.
Stoichiometry is a method