Chapter Fifteen: Redox Equilibria and Electrochemistry

Chemicals:

1. 1 M copper sulfate

249.7 grams CuSO₄ · 5 H₂O per liter

2. 1 M zinc sulfate

287.5 grams ZnSO₄ · 7H₂O per liter

3. 1 M tin (II) chloride

Dissolve 226 grams SnCl₂ · 2H₂O in 170 mL conc. HCl

Dilute to 1 liter with water

Make fresh each semester

4. 1 M magnesium sulfate

246 grams MgSO₄ · 7H₂O per liter

5. 1 M lead nitrate

331.2 grams Pb(NO₃)₂ per liter

6. 1 M iron (II) sulfate

10 mL conc. H₂SO₄ and 278 grams FeSO₄ · 7H₂O per liter

•Doesn't keep very well; if solution turns brown, discard. Solution should

be green.

7. 1 M aluminum chloride

241.4 grams AlCl₃ · 9H₂O per liter

8. 0.1 M silver nitrate

17 grams AgNO₃ per liter

9. 1 M potassium nitrate

101 grams per liter

10. 0.2 M dimethylglyoxime

12 grams per liter 95% ethanol

11. 3% hydrogen peroxide

12. 1 M ammonium thiocyanate

76 grams per liter

13. 1 M sulfuric acid

56 mL conc. H₂SO₄ per liter

Carefully add the acid to the water with stirring.

14. 0.06 M ferrous ammonium sulfate in 1 M sulfuric acid

Use a volumetric flask:

22.528 grams Fe(NH₄)₂(SO₄)₂ · 6H₂O per liter, dissolved in 1 M H₂SO₄

15. 0.01 M ceric ammonium sulfate in 1 M sulfuric acid

Use a volumetric flask:

6.326 grams Ce(NH₄)₄(SO₄)₄ · 2H₂O per liter, dissolved in 1 M H₂SO₄

16. 0.002 M potassium dichromate in 1 M sulfuric acid

Use a volumetric flask:

0.588 grams K₂Cr₂O₇ per liter,

dissolved in 1 M H₂SO₄

17. Ferroin indicator

Purchased 0.025 M 1,10-

phenanthroline ferrous sulfate solution

•Dilute 1 part indicator with 2 parts water

18. Diphenylamine sulfonate indicator

•Dissolve: 0.16 grams barium diphenylamine sulfonate in 100 mL water

•Add: 0.5 grams Na₂SO₄

•Filter: Whatman #42

19. Metals: cut 1/4" square

(Metal foils are available from VWR.)

a. Copper foil; .005" thick

b. Zinc foil; .010" thick

A good source:

Strem Chemicals, Inc.

Dexter Industrial Park

7 Mulliken Way

Newburyport, MA. 01950-4098

c. Lead foil; .008" thick

d. Tin foil; .005" thick

e. Magnesium ribbon

f. Iron wire or nails

You can get ungalvanized nails at a hardware store.

g. Aluminum foil

Can use heavy duty foil from grocery store.

h. Silver wire, 24 gauge

A good source is:

D. F. Goldsmith

907 Pitner Avenue

Evanston, Illinois 60202

(ph. 312-869-7800)

We require the students to recycle the Ag.

20. Lead metal strips

Cut 1/4" x 1"

21. Aluminum foil, heavy duty

3 inches square

22. Whatman 3 mm chromatography, 2 cm square This comes in a roll 2 cm x 100 m.

23. Filter paper, 1/2" x 2"

Use the scraps from Chapter 18.

Supplies:

1. Whatman #3, 9 cm

2. Cotton swabs

3. Pencil lead

.5 mm 6H leads, approx. 1 inch long

4. Copper wire

0.02" diameter, cut approx. 1 inch long

5. Digital multimeters

Plus spring clip attachment. If you do not have the attachments, the electrical leads used for the first part of the experiment will work.

6. Microtowels

7. Waste containers

8. A few nickels

Per Student:

3 - Empty large drop microburets

1 - Petri dish

1 - 9V battery

2 - Electrical leads

1 - Wash bottle

1 - Waste cup

From Student Kit:

2 - 24-well trays

2 - 1 x 12 well microstrips

Lab top

Tweezers

Hand lens

Scissors

Ruler

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