

![]() | Project title | Disinfectant concentration and bacteria resistance
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| Difficulty Level | High school | |
| Project page |  Click here to view this science project | |
Description | ||
| The aim of this science fair project is to find out how the concentration of disinfectants can affect bacteria resistance. The experiment is carried out using different concentrations of Dettol disinfectant. | ||
Instructions preview | ||
| 1. The independent variable for this experiment is the concentration of dettol disinfectant used – 25%, 50% and 75%. The dependent variable is the size of the inhibition zone which refers to the area free of bacteria). This is determined by measuring its diameter using a ruler. The constants (control variables) are room temperature, amount of sunlight and the ingredients in the Petri dish agar. 2. Prepare 12 Petri dishes of agar and store them in the refrigerator. 3. Three Petri dishes are taken out of the refrigerator and allowed to attain room temperature. Label the dishes - 25%, ..... | ||