Question

1. Calculate the theoretical yield of the solid precipitate. Show your work.

mass of CaCl₂ =2.0 g

Molar mass of CaCl₂ = 110.98 g/mol

Moles of CaCl₂ = 2.0 g * 1 mol/110.98g = 0.018 mol

Mass of K₂Co₃ =2.0 g

Molar mass of K₂Co₃ = 138.205 g/mol

Moles of K₂Co₃ =2.0 g * 1 mol/ 138.205g =0.0145 moles

According to balanced equation 1mole of CaCl₂ reacts with 1 mole of K₂CO₃

Thus, 0.018 moles of CaCl₂ will react with = 0.018 moles of K₂CO₃

Thus, 0.0145 moles of K₂CO₃ will produce 0.0145 moles of CaCO₃

Molar mass of CaCO₃ = 100.0869 g/mol

Theoretical yield of CaCO₃ = moles of CaCO₃ * molar mass of CaCO₃

Theoretical yield of CaCO₃ = 0.0145 moles * 100.0869 g/mol =1.45 g

1. Use Question 1 to calculate the percent yield of the solid precipitate. Show your work.

1.45 g = 1.45/100.0869

=0.0144 moles

Therefore, % yield= 0.0144/0.018

=80%

1. Based on your yield of calcium carbonate, calculate the mass of calcium present in the original solution.
2. Analyze the data and use your yield of calcium carbonate to determine the experimental concentration of calcium chloride in the solution that you made in steps 6 and 7. Show all calculations and report in % wt/v concentration.
3. Calculate the theoretical concentration of calcium chloride in the solution that you made up in steps 6 and 7. Show all calculations and report in % wt/v concentration.
4. Using your answers from questions 4 and 5, create a bar graph comparing the theoretical to experimental percent concentrations of calcium chloride in the solution. Then, calculate percent error between the two concentrations.

Table 1: Data and Observations

Material	Mass
CaCl2	2.0
K2CO3	2.0
Filter Paper	2.3
Watch Glass	37.3
Filter Paper + Watch Glass + Precipitate	8.6
Precipitate	1.7

Table 2: Mass of CaCl₂ after 24 Hours

	Initial Observations	24 hour Observation
weigh Boat	2.2	5.4
CaCl2	2.0	3.2

Answer 1