Which gas is liberated when dilute hydrochloric acid reacts with zinc metal ? Write a balanced chemical equation for the reaction which takes place. How will you test this gas ? Name a metal which produces the same gas just by reacting with cold water.

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?