What is the ecological principle behind the biological control method of managing with pest insects ?

Write the principle behind the method hydraulic washing.

Indicate the principle behind the method used for the refining of zinc.

What is the principle behind calculating molar conductivity of weak electrolytes?

Outline the principle behind the refining of metals by the chromatographic method.

Write the principle behind the froth floatation process. What is role of collectors in this process?

The use of biological methods for controlling plant diseases and pests is called ...

Read the following statements and select the correct option. Statement 1 : Biocontrol refers to the use of biological methods for controlling plant diseases and pests. Statement 2 : Use of biocontrol measures will greatly reduce our dependence on toxic chemicals and pesticides.

What is the device in which the thermal properties of a substance can be measured applying the principle of measurement of heat by method of mixtures ?