Identification of Dependent, Independent and Controlled Variables

Independent Variable:

• Different types of liquid used to grow each plants

• In the process of the experiment

• Before the experiment has started

Dependent Variables:

• Appearances of the plants after being exposed to liquids of different pH values

• In the process of the experiment

• After the experiment has ended

Controlled Variables:

• Water hyacinths

• pH values of each liquids

• Type of container

• Amount of liquids and water to grow the plants