2.1 Equipment list
  • 6 Clean Beakers (250 ml)
  • 5 different Colored Lights (Blue, Green, Yellow, Red, White)
  • 6 Test Tubes
  • 6 Funnels
  • 500g of Cabomba
  • 6 Opaque Boxes
  • 1 Ruler
  • 10L of 1% Bi-carbonate water
  • Electric Supply
  • Data logger with light sensor
  • 2 Plastic Beakers

2.2 Diagrams of experimental setup  

2.3 Procedures
Set up the experiment as shown in the diagram above. (6 setups)
  1. Measure each Cabomba making sure that all of them are of equal length, 8 cm and mass, 1.7g (2 s.f)
  2. Place the Cabombas in the funnels.
  3. Place the funnels upside down in the breakers.
  4. Fill the beakers with water (1% bicarbonate) till the tip of the funnel is fully submerged.
  5. Fully fill the test tubes with water (1 % bicarbonate).
  6. Cover the mouth of the test tubes and gently place the test tubes in the beaker, onto the tip of the funnel, making sure that there are no water displacement in the test tubes.
  7. Place 5 setups each with cabomba inside the opaque boxes with led strips attached in them. Place the last setup in an opaque box, ensuring that no light passes through.
  8. Seal the box so that no light from the outside can enter.
  9. Measure the water displacement in the test tubes after 3 days.

2.4 Risk Assessment and Management  
As this experiment involves glass beakers, avoid breaking it to reduce the risk of being cut. As we are using led lights, we must be careful not to look at the lights for a long period of time as it can cause damage to our eyes. Make sure hands are dry when in contact with the electric lamps. Keep water and plant containers away from electric plugs.

2.5 Data Analysis
Tabulate the data and calculate the average growth of the Cabomba then plot a graph of the average height of the Cabomba against the light in which it was grown in. From the graph, we can find out which colour of light is the best for making cabomba grow the most. (The aim)

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