What colour change does phenolphthalein undergo in nitric acid? What occurs when nitric acid is added to the water? What colour is the universal indicator in nitric acid? What reaction does nitric acid undergo with sodium carbonate?

What type of questions asked from the lesson of magnetic effect of electric current 

Wavelength of green light is

A) 400-450 nm

B) 500-550 nm

C) 660-720 nm

D) 720-800 nm

What is the difference between anaerobic & aerobic respiration? Name some organism that uses the aerobic mode of respiration?

What are the main components of our environment? Explain each of them briefly.

What are examples of hydrotropism plants?