Making a Dilution Series

Aim : To make a dilution series to investigate concentration

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

Method:
 
    1. Place the six test tubes in a test tube rack, Label the rack with numbers 1- 6.
    2.Using the measuring cylinder, fill the the test tube 1 with 10 mL of water. Fill the remaining 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 the 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 tubes 4, 5 and 6.

Results

With each transfer it got lighter


Discussion:

We first added the solute into the solvent. Then we made an solution.Then we diluted the first solution by taking 5 ml of the solution and diluting it in the 5 other solvents and then we've got a dilution series.We saw that the 1st solution was the most concentrated and the last solution was less concentrated