Lab 5b

Objectives-

• Observe a variety of chemical experiments
• Interpret and explain observations with the balanced equations
• Classify each reaction as one of the four main types.

Supplies-

Equipment

• Bunsen Burner
• 6 test tubes
• one will be flame heated
• Test tube clamp\Medicine dropper
• Wooden splint
• Crucible tongs
• Steel wool
• Safety goggles
• Lab apron

Chemical Reagents

• Bare copper wire
• Iron nail
• 0.5M copper (II) sulfate solution
• Solid copper (II) sulfate pentahydrate
• 0.5M calcium chloride solution
• 0.5M sodium carbonate solution
• Mossy zinc
• 2M hydrochloric acid solution
• Hydrogen peroxide solution (6%)
• Manganese (IV) oxide

Procedure-

• Put on Lab apron and goggles
• Make observations before, during and after.

Reaction 1

• Adjust burner to high heat
• Use crucible tongs to hold 6cm copper wire over hottest part of flame for a few minutes

Reaction 2

• Clean iron nail with steel wool until shiny
• Place nail in test tube. Add copper (II) sulfate solution until nail is half covered
• After 15 minutes, remove and observe

Reaction 3

• Put solid copper (II) sulfate pentahydrate in test tube until one third full
• Test tube must be heat resistant
• Heat test tube, gently angled away from self and classmates, slowing moving back and forth over the flame
• Continue heating until no more changes occur
• Save contents for reaction 4

Reaction 4

• Allow test tube from reaction 3 to cool
• Add 2-3 drops of water with medicine dropper
• Record observations

Reaction 5

• Fill a test tube one quarter full with calcium chloride solution. Fill a second test tube one quarter full with sodium carbonate solution
• Pour calcium chloride solution into test tube containing sodium carbonate solution
• 
  

Reaction 6

• Put mossy zinc in test tube
• Add hydrochloric acid until zinc is covered

Reaction 7

• Fill half a test tube with hydrogen peroxide
• Add a SMALL amount of manganese (IV) oxide
• Test gas by placing a glowing splint into mouth of test tube

• Wash hands with soap and water

Table 1-

Analysis of Results-

1. Oxygen
2. That a reaction occured betwen the Fe and the CuSO4
3. In reaction 3, there was a change of color and consistency, and in reaction 4 there was an exothermic reaction
4. Na2CO3 + CaCl2 -> 2NaCl + CaCO3 therefore calcium carbonate
5. Use the glowing splint test to check for combustion
6. 
   
1. It was oxygen
2. H2O2 + MnO2 -> H20 + MnO2 + O2 therefore the liquid is H2O

Follow Up Questions-

1. 1CdSO4 + 1Zn -> 1Cd + 1ZnSO4
2. 2H2O ->2H2 + 1O2
• Decomposition

Conclusion-

1. 2Cu + O2 -> 2CuO     Synthesis
2. 2Fe + 3CuSO4  -> Fe(SO4)3     Synthesis
3. 1CuSO4 • 5H2O ->  1CuSO4 + 5H2O     Decomposition
4. 1CuSO4 + 5H2O ->  1CuSO4 • 5H2O     Synthesis
5. 1CaCl2 + 1Na2CO3 -> 1CaCO3 + 2NaCl     Double Replacement
6. 1Zn + 2HCl ->1ZnCl2 +1H     Single Replacement
7. H2O2 + MnO2 -> H2O + MnO2 + O2 (Will somehow figure this out later)

And, to continue our new tradition: The chemistry cat of the day