Stoichiometry and Limiting Reactant

Stoichiometry and Limiting Reactant

(An Experiment in Chemistry 1)

[pic 1][pic 2]

Echon, Ivan Lito Boy C.

11- Campos

Procedures

1. Compute the amount, in g. of solid product produced when 0.50 g of sodium carbonate and 0.50 g of calcium chloride are mixed.
2. Weigh 0.50 g of sodium carbonate (Reactant A) and 0.50 g of calcium chloride (Reactant B).
3. Observe the properties of both reactants.
4. Dissolve both reactants in 10.00 mL (or greater) water. They must be in separate containers.
5. Observe the properties of both solutions.
6. Mix the two solutions. Let it stand for at least 5 minutes.
7. Use a separation technique to separate any precipitate formed.
8. Dry the precipitate.
9. Weigh the precipitate.
10. Separate the components of the remaining liquid in the mixture.
11. Observe the properties of separated components.

Data:

Reactant A: Sodium Carbonate (Na2CO3)

        Mass of reactant A: .50 g

        Properties of reactant A: solid, white

        Properties of reactant A (aqueous solution): translucent

Reactant B: Calcium Chloride (CaCl2)

        Mass of reactant B: .50 g

        Properties of reactant B: solid, crystal

        Properties of reactant B (aqueous solution): less clear

Chemical Equation [pic 3]

Limiting reactant: Calcium Chloride (CaCl2)

Precipitate: CaCO3 Calcium carbonate .31g was produced after the filtration

Actual and theoretical: .31g CaCO3/ .45g CaCO3

% Yield: 68.89%

Discussion and Conclusion

Following all the procedure, letting the precipitate dry on a petri dish. Students weigh the precipitate and we actually get 2.23g but the mass of the filter paper is included so we diminished the mass of the filter paper which is 1.92g. We get the mass of the precipitate having a .31g. The actual mass is really lesser than the theoretical mass. Doing the filtration there is actually an error in putting the aqueous in the flask with filter paper not all of the precipitate is obtained. And in weighing the precipitate there is a tendency that the precipitate will be spilled due to carelessness. Thus, I conclude that human errors in the process of the filtration in weighing affects the mass of the precipitate significantly. Also, we use a tap water in making a aqueous solution so this behavior might be a reason in getting a lesser mass of the precipitate.