Honors Chemistry Chapter 12 Stoichiometry Lab Name ______Per_____
Lab is due on: ______
Purpose:To investigate the quantitative reaction between copper and silver nitrate.
Procedure:
Day one
1. Form a coil of copper wire leaving about 5 cm straight for use as a handle. Weigh the coil and list its weight here: ______g
2. Put a label with the names of the members of the lab group on a clean, dry 250 mL beaker. Record its weight here: ______g
3. Weigh the full vial of silver nitrate (approximately 1-1.5 g of AgNO3) and list its weight here: ______g.
Empty the vial into the 250 mL beaker and record the weight of the empty vial
here: ______g. List your vial number here: # _____.
4. Fill the beaker approximately ½ full with deionized water. Stir until all of the crystals have dissolved. Place the copper wire in the solution with the straight handle sticking out of the solution. Cover the beaker with a paper towel and set it aside until tomorrow.
Day two
1. Observe the beaker and its contents. What do you see? ______
______.
2. Shake the crystals off of the coil into the remaining solution. Using deionized water, rinse off any crystals adhering to the coil. Set the coil aside to dry on a paper towel. Weigh the coil when it is dry. Record its weight here: ______g
3. Allow the crystals to settle. Weigh a piece of filter paper.
Record its weight here: ______g Fold the paper in half and then in half again so that it looks like ¼ of a circle. Open the paper so that 3 flaps are on one side and one flap is on the other so that you now have an open cone. Place the open cone inside of a plastic funnel.
4. Hold the funnel over a sink. Decant (pour off the liquid while leaving the solid behind in the beaker) the solution through the filter paper in the funnel. Add about 5 mL of silver nitrate solution to the beaker to dissolve any flecks of copper. Decant again. Add about 10 mL of deionized water to the beaker and decant again. Do this washing of the crystals two more times with the deionized water.
5. Place the wet filter paper in the beaker with the wet silver. Put the beaker in the oven to dry overnight.
Day three
1. Weigh the dry silver, beaker, and filter paper all together. Record the weight here: ______g.
Data and Calculations: Show all work! Round to appropriate significant Figures!!!!!!
1. Grams of silver nitrate: ______g
2. Grams of silver obtained: ______g
3. Grams of copper reacted: ______g
4. Moles of copper reacted: ______
5. Moles of silver obtained: ______
6. Ratio of moles of silver to moles of copper: ______
7. Atoms of copper reacted: ______atoms
8. Atoms of silver obtained: ______atoms
9. Ratio of atoms of silver to atoms of copper: ______
10. How do your answers in #6 and in #9 compare? Explain why: ______
______
______.
11. Ratio of weight of silver to weight of copper: ______. Is this important? Why or why not? ______
______.
12. Write a balanced equation for the reaction using all appropriate symbols:
13. Do your ratios from #6 and #9 agree with the coefficients from the balanced equation? ______.
14. Assuming that all of the silver nitrate reacted, do a stoichiometry problem that determines how much silver ( in grams) you should have obtained (theoretical yield). Show the work below.
15. Calculate the percent yield for the reaction using your theoretical yield from #14 and your actual yield from #2. Show the work below.
16. Calculate % error. Show the work below.
17. In this experiment, ______is the limiting reactant and the excess reactant is ______.
Lab report requirements: Turn in this paper with all calculations shown and staple a piece of loose-leaf paper with a theory and discussion section.