Types of Chemical Reactions Lab
The purpose of this lab is to determine types of reactions with only the reactants and through observation. Through observing the experiments, one is able to see a visual of each type of reaction taking place and it gives them a better understanding of how chemical reactions work and what products they may form.
Materials & Procedure
* Wood Splints- Copper Sulfate
* Sodium Sulfate- Copper Wire
* Barium Chloride- 6% Hydrogen Peroxide
* Mossy Zinc- Copper Sulfate Pentahydrate
* Hydrochloric Acid- Iron Filings
* Manganese Dioxide
Place a scoop of copper (II) sulfate pentahydrate crystals in a clean, dry test tube. Use a test tube holder to position the test tube over a burner flame. Heat until no further change is observed. Allow dehydrated crystals to cool and add 5 drops of water.
Place 1 squirt of sodium sulfate in a test tube. Add a squirt of barium chloride solution.
Using crucible tongs, heat a 5 cm piece of copper wire to red heat for 30 seconds in the hottest part of the burner flamer. After the wire cools, scrape its surface with the edge of a scoopula.
Place a small piece of mossy zinc in a test tube and add enough hydrochloric acid so that the mossy zinc is completely submerged. Then insert a burning splint into the mouth of the test tube.
Fill one third of a test tube with hydrogen peroxide. Use a scoopula to add a match head sized amount of manganese dioxide. Then insert a glowing splint into the mouth of the test tube.
Place iron filings in a test tube and cover them with copper (II) sulfate solution. After several minutes, pour off the liquid, dump out the iron filings and examine them.
Reaction| Observations Before Reaction| Observations After Reaction| A| CuSO4x5H20 is crystal, light blue in colour.| CuSO4 turned white when heated.CuSO4 turned back to original blue colour when H2O was added. Clear liquid formed on side of the test tube.| B| Na2SO4 & BaCl are both a clear liquid.| When BaCl was added to Na2SO4, a milky white precipitate formed.| C| Copper wire is solid, reddish brown in colour.| Copper wire turned black.When scraped with scoopula, a reddish brown colour was revealed under the black crust.| D| Zn is solid, silver in colour.HCl is a clear liquid.| HCl bubbled when added.Flaming splint made a popping noise and was extinguished when inserted.| E| H2O2 is a clear liquidMnO2 is a fine black powder| H2O2 bubbled when MnO2 was added.Glowing splint was relit.| F| Fe is solid, silver in colour.CuSO4 is a liquid, blue/green in colour.| Iron filings turned reddish brown in colour when added to CuSO4 solution|
Sources of Error
During experiment/reaction A, the test tube filled with copper (II) sulfate pentahydrate fell onto the ground and the contents were allowed to cool before being placed back onto the burner flame.
During experiment F, the iron filings were not left in the CuSO4 solution for the suggested amount of time so the reaction may not have been complete.
2. Based on observations, the non-solid product formed when copper (II) sulfate pentahydrate was heated is assumed to be water. Also based on observations, the solid substance remaining in the test tube after heating is assumed to be CuSO4.
3. If, in part B, one of the products is sodium chloride then the other product is likely barium sulfate.
4. Copper combined with oxygen gas from the atmosphere to form the observed product.
5. On the basis of the glowing splint test, it can be determined that the other product formed when manganese dioxide is added to hydrogen peroxide is oxygen gas, because the glowing splint was relit.
6. Word Equations
A. Part 1. Crystals of copper (II) sulfate...