Magnesium is an element of group 2 of the periodic table. It forms compounds such as (i) magnesium oxide, MgO, (ii) magnesium hydroxide, Mg(OH)_2, (iii) magnesium sulphate, MgSO_4 and (iv) magnesium chloride, MgCl_2. Calcium is also an element of group 2. Write the formulae of calcium oxide, calcium hydroxide, calcium sulphate and calcium chloride.

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?