Description of the experiment
* Aim:To observe the reactions of sulfuric acid as an oxidising agent and as a dehydrating agent. Equipment:
* 20mL of concentrated sulfuric acid
* 20mL of 2mol/L sulfuric acid
* 2 small pieces of each of copper, zinc and iron
* 10 test tubes
* Test tube rack
* 2g of sugar crystals (sucrose)
* 2 wooden ice-cream sticks
* 10mL measuring cylinders
A: Sulfuric acid as an oxidising agent
1. Clean pieces of metal with sandpaper to remove oxide coating. 2. Add a piece of each metal to a separate test tube.
3. Add 5mL of concentrated sulfuric acid to each test tube. 4. Record the observations.
5. Repeat the experiment with 2mol/L sulfuric acid.
B: Sulfuric acid as dehydrating agent
1. Place 1g of sugar (sucrose) and a wooden ice-cream stick into separate test tube. 2. Add 1-2mL of concentrated sulfuric acid to each test tube. 3. Record the observations.
4. Repeat the experiment with 2mol/L sulfuric acid
* Conc. sulfuric acid is highly corrosive
* If conc. Sulfuric acid is spilt, do not add water
* Hydrogen sulfide gas
| Conc. Sulfuric acid| 2 mol/L sulfuric acid|
Copper| No observable change| No observable change|
Zinc| No observable change| No observable change|
Iron| * Exothermic reaction * Bubbling gas| No observable change| Sugar| * Exothermic reaction * Black solid is produced and pushed out from the test tube * Gas with rotten egg smell is released| No observable change| Wood| * Black layer is formed on the wood| No observable change| Validity and reliability
* Experiment was not repeated
* Low reliability
* Results not consistent with the known theory
* Require to eliminate experimental errors
Analysis of the results