9Hh Science: Making a Dilution Series

Aim: To make a dilution series to investigate the concentration.

Equipment: A potassium permangante crystal, six large test tubes, tweezers, a plastic transfer pipette, a test tube rack, 10ml measuring cylinder.

Method:

1. Place the six test tubes in a test tube rack. Lable the rack with numbers 1-6 
2. Using the measuring cylinder, fill test tube 1 with 10 ml of water. Fill remaining test tubes with 5 ml of water.
3. Using your tweezers, add a single crystal of potassium permanganate to test tube 1.
4. Gently shake the test tube until the crystal has dissolved.
5. Using the transfer pipette, carefully remove exactly 5 ml from test tube 1 and pour it into test tube 2.
6. Rinse the transfer pipette thoroughly to ensure that no purple solution remains.
7. Gently shake test tube 2 and repeat the transfer process, transferring exactly 5 ml of solution from test tube 2 to test tube 3.
8. Rinse the pipette again and repeat the transfer process for test tube 4, 5, and 6.

Results:

What I saw from this experiment is that each one of them changed colour dark to light. This didn't go as planned but at least it was done, This experiment was quick, simple, easy. The Colour in the test tubes in the rack was light/dark Purple. 

Conclusion: 

The concentration of the test tubes was weakening.