Basic Science Experiments

Posted on Aug 1, 2024 in Chemistry

Experiment 1: Electrolysis

Materials:

  • Container
  • Dilute sulfuric acid
  • Two electrodes (e.g., copper and zinc, carbon and iron)
  • Galvanometer
  • Wires

Procedure:

  1. Fill the container with dilute sulfuric acid.
  2. Arrange two electrodes in the electrolyte so that they are vertical and at a distance from each other.
  3. Connect a galvanometer across the plates by means of two wires.
  4. Note the reading indicated by the galvanometer deflection.
  5. Wait for a short time.
  6. Observe the action of the acid and the electrodes.
  7. Remove the electrodes from the container.
  8. Disconnect the wires.
  9. Replace the initial electrodes with a different pair of electrodes (e.g., replace copper and zinc with carbon and iron).
  10. Reconnect the galvanometer.
  11. Read the value of the galvanometer deflection.
  12. Compare this value with the value obtained for the previous pair of electrodes.

Observations:

  • The electrodes should be removed from the container, and the wires disconnected.
  • The initial electrodes should be replaced with the second pair of electrodes.
  • The galvanometer should be reconnected, and the value of the deflection should be noted.
  • The value of the deflection should be compared with the value for the initial electrodes.

Experiment 2: Freezing Point Depression

Materials:

  • Ice
  • Common salt
  • Large container
  • Calorimeter
  • Hot water
  • Mercury thermometer

Procedure:

  1. Crush some ice and mix it with a small amount of common salt to produce a freezing mixture.
  2. Place this freezing mixture in a large container.
  3. Pour a small amount of hot water into a calorimeter and insert this calorimeter into the freezing mixture.
  4. Allow the water to cool, and by means of a mercury thermometer, take readings of the temperature of the water at regular intervals. Note the temperature at every reading. The water should be stirred continually throughout the experiment.
  5. Continue the experiment until the temperature of the water is well below 0°C. Observe carefully what happens to the water as the temperature approaches 0°C. Continue stirring the water and noting the temperature for several minutes after ice forms in the calorimeter.
  6. From the results, plot a graph of temperature against time.
  7. From the graph, and from the observations made during the experiment, attempt to make deductions about what takes place when the temperature of water is lowered.

Experiment 3: Distillation

Materials:

  • Thermometer
  • Stopper
  • Bunsen burner
  • Condenser with two tubes (one at the top and one at the bottom)
  • Cool water
  • Beaker
  • Tripod

Apparatus Functions:

  • Thermometer: To measure the temperature of the solution.
  • Stopper: To hold the thermometer.
  • Bunsen burner: To heat the liquid.
  • Tube at the top of the condenser: To conduct the cool water away.
  • Cool water: To cool the vaporized alcohol.
  • Tube at the bottom of the condenser: To conduct cool water in.
  • Beaker: To collect the condensed alcohol.
  • Tripod: To support the apparatus.