Why is purification of water and nutrient salts so important in studies involving mineral nutrition using hydroponics?

What is meant by water table? Why is it important?

Give reason : Water is not used to control fire involving electrical equipment.

Why is it important for us to have iodised selt in our diet ?

Why is the use of iodised salt advisable ?

Choose the correct option Mycorrhiza is a symbiotic association of fungus with root system which helps in A . absorption of water B . mineral nutrition C. translocation D .gaseous exchange.

Why should we avoid using plastic bags or throwing them in water bodies or on the road?

The process that you see is used for purification of copper. A thin plate of pure copper and a thick rod of impure copper are used as electrodes. Copper and impure rod is sought to be transferred to the thin copper plate. Which electrode should be attached to the positive terminal of the battery and why ?