1. SURVEY OF CHEMISTRY LABORATORY I
CHEM 1151L
REACTIONS OF COPPER

2. CAUTION!!!
BE SURE TO WEAR SAFETY GLASSES AT ALL TIMES IN THE LABORATORY NO EXCEPTIONS TO THIS RULE!

3. REACTIONS OF COPPER
- To demonstrate chemical changes - To investigate the reactions of copper and its compounds - Students will make a series of compounds with metallic copper and regenerate the elemental copper at the end Cu → Cu(NO3)2 → Cu(OH)2 → CuO → CuSO4 → Cu

4. USES OF COPPER
Copper metal is used for - Water pipes - Electrical wiring - Cookware - Coins - Etc There are extensive uses of the compounds of copper - Widely used as pigments - Copper sulfate (CuSO4) is a fungicide

5. SAMPLES OF COPPER AND ZINC

6. PREPARATION OF COPPER(II) NITRATE
- Weigh about 1 gram of copper metal - Cut with scissors - Roll into a ball - Record your observation of the copper metal

7. PREPARATION OF COPPER(II) NITRATE
3Cu + 8HNO3 → 3Cu(NO3) NO + 4H2O
- Work in the hood - Add 10 mL of 16 M nitric acid (HNO3) into a clean 250mL beaker - Place the metal copper into the beaker of acid

8. PREPARATION OF COPPER(II) NITRATE
- Allow the copper to completely dissolve

9. PREPARATION OF COPPER(II) NITRATE
- Warm the solution gently to remove excess nitric acid (brownish-red gas) - Stop warming after all traces of brownish-red gas are gone - Avoid excessive boiling

10. PREPARATION OF COPPER(II) NITRATE
- Observe and record the properties of copper(II) nitrate - Use litmus paper to test acidity of solution - Blue litmus paper will turn red if solution is acidic

11. PREPARATION OF COPPER(II) HYDROXIDE
Cu(NO3) NaOH → Cu(OH) NaNO3
- Allow the beaker to cool - Place the beaker in an ice bath - Add 15 mL of 6 M sodium hydroxide (NaOH) dropwise with stirring

12. PREPARATION OF COPPER(II) HYDROXIDE
- Use litmus paper to test if solution is basic - Add a drop of the mixture to a strip of red litmus paper - Blue color indicates the solution is basic - The solution itself is blue so watch the “bleeding” portion

13. PREPARATION OF COPPER(II) HYDROXIDE
- Add more NaOH as necessary (drop by drop) until the solution is basic - Rinse stirring rod into the solution when being removed from the solution - Rinse the sides of the beaker into the solution - Record all observations

14. PREPARATION OF COPPER(II) OXIDE
Cu(OH)2 + heat → CuO + H2O
- Add 50 mL of distilled water to the beaker containing Cu(OH)2

15. PREPARATION OF COPPER(II) OXIDE
- Gently boil the solution while stirring continuously - Boil for an additional minute after a distinct color change is observed - Record all observations

16. PREPARATION OF COPPER(II) SULFATE
CuO + H2SO4 → CuSO4 + H2O
- Allow CuO to settle - Pour off the clear liquid into another beaker - Be careful not to lose any of the solid material (CuO) - Add 50mL of distilled water and stir - Pour off the water once settled - Repeat the process twice

17. PREPARATION OF COPPER(II) SULFATE
- Stir the mixture - Add concentrated sulfuric acid (H2SO4) dropwise until all of the CuO dissolves - A distinct color change will be observed - Record all observations

18. PREPARATION OF COPPER(II) SULFATE
- Add about 3 grams of zinc to the CuSO4 solution - Cover the solution with Parafilm - Store it in a cabinet

19. END OF FIRST LAB PERIOD

20. PREPARATION OF COPPER
CuSO4 + Zn → Cu + ZnSO4
- Solution should turn from blue to colorless after all copper has reacted

21. PREPARATION OF COPPER
CuSO4 + Zn → Cu + ZnSO4
- Stir for solution to become colorless if the solution is still blue - Consult instructor before advancing to the next step

22. PREPARATION OF COPPER
Zn + 2HCl → H2 + ZnCl2
- Work in the hood - Slowly add 5-10 mL of 12 M hydrochloric acid (HCl) to the solution

23. PREPARATION OF COPPER
- Remove excess pieces of zinc with forceps - Use a wash bottle of distilled water to rinse the copper off the pieces of zinc as they are removed - Mass and record a piece of filter paper and Petri dish together

24. PREPARATION OF COPPER
- Allow the copper to settle - Place the filter paper in a Buchner funnel

25. - Filter the solution through the Buchner funnel
PREPARATION OF COPPER
- Filter the solution through the Buchner funnel

26. PREPARATION OF COPPER
- Allow the funnel to drain completely - Wash the copper with distilled water followed by acetone - Use small amounts

27. PREPARATION OF COPPER
- Place the filter paper and copper on the massed Petri dish - Dry it in the oven for a few minutes - Make sure the filter paper does not burn - Remove immediately when filter paper starts to turn brown

28. PREPARATION OF COPPER
- Remove sample from oven and allow to cool - Mass copper together with filter paper and Petri dish - Determine the mass of the copper recovered in your experiment - Calculate percent recovery

29. CLEAN UP
- Dispose of copper into the appropriate waste container - Clean all glassware - Return all equipment to their proper places