Lab 3 -Wh at Changes During a Chemical Reaction? For this lab we will be looking

Question

Lab 3 -Wh at Changes During a Chemical Reaction? For this lab we will be looking at how mass is 2 trials of the same experiment, and then the out a copy of the final set of class data to be included in your Be sure to print trials of the same exsolin at how mass is affected during chemical reactions. You will be conducting t, and then the class results will be collected and shared. your report. In this lab we will be looking the reaction of that product with sulfuric acid. Make sure and accurately record the mass at each step. at the reactions between sodium carbonate and calcium chloride, and then that you thoroughly record your observations, Procedure: Obtain 2 vials and ca thend caps from the front cart, and label one for the calcium chloride solution, and the other for the sulfuric acid. .Add 10 mL of 1 Molar sodium carbonate solution to a 125 mL flask * Add 3 mL of 3 Molar sulfuric acid solution to the appropriate vial and cap the vial . Add 3 mlL of 3 Molar calcium chloride solution to the appropriate vial and cap the vial . Use a rubber band to attach the 2 vials to the flask, dry the exterior of each with a paper towel, and then take their collective mass using an analytical balance (the balance with glass windows). Take all three back to your lab station and slowly add the contents of the calcium chloride vial to the flask containing the sodium carbonate. Swirl gently to mix o Let sit for 3-5 minutes Using the same balance record the new collective mass. At your station: add the sulfuric acid carefully to the flask. Swirl vigorously After the solution has been swirled off and on for 10 minutes record the new mass. . Using the same balance record the new collective mass. . Repeat the experiment. Data: At the end of this experiment you should have 3 mass values from both experimental runs. Record them in the common class spreadsheet.

Explanation / Answer

1. The first reaction where CaCl2 was added to Na2CO3, a white solid formed.

CaCl2 (aq) + Na2CO3 (aq) --------> NaCl (aq) + CaCO3 (s)

In the second reaction where sulfuric acid was added to CaCO3, bubbles of CO2 appeared.

CaCO3 (s) + H2SO4(aq) -----> CaSO4 (aq) + CO2 (g) + H2O(l)

These two are the visible evidences that show there was chemical reaction taking place.

-----------------------------------------------------------------------------------------------------------------------------------------------------------------

2. The mass after the second reaction was taken after some time to allow the precipitate CaCO3 to react completely with sulfuric acid and to allow all the CO2 to escape out. If the mass was taken after 1 minute, the readings would nto have been consitent as the reaction would not be complete.

---------------------------------------------------------------------------------------------------------------------------------------------------------------------

3. If we added sulfuric acid to Na2CO3, the following reaction would take place:

Na2CO3 (s) + H2SO4(aq) -----> Na2SO4 (aq) + CO2 (g) + H2O(l)

Bubbles of CO2 would be released in the first step. So there would be variations in mass measurements too as CO32- is being converted to CO2 gas in the first step.

Related Questions

Navigate

• Browse (All)
• Browse L
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.