The vertical blocks in a table is known

When water itself combines chemically with some element or mineral it is called 

Conduction band electrons have more mobility than holes because they

Wood spirit is

The most abundant constituent of atmospheric air is

Which one of the following is known as the brown coal?

The process of covering water pipes made of Iron with Zinc layer to prevent corrosion is called: 

The function of skimming tank in sewage treatment is to remove 

The electronic configuration of an atom having atomic number 20 is 

Burning pyrites ore gives out 

Find the odd one: