Which medieval Indian ruler started the system of

Nitrous Oxide (N2O) is also known as –

Which of the following is not the Ore of Aluminium?

Which of the following elements is a noble gas?

Which vitamin exists  in the Cobalt   ?

Which mineral is the ore Of aluminium ?

Sphalerite is an ore/mineral of -

Which substance is present in green leaves to help in the process of photosynthesis?

Which fossil fuel is formed under earth by the decomposition of vegetable matter lying under water by anaerobic bacteria in the absence of oxygen?

Formation of Sodium Chloride is an example of

Carbohydrates are organic compounds composed of which elements?