Classification ...

Which configuration represents a noble gas

Which of the following pair has elements containing same number of electrons in the outermost orbit

The electronic configuration of an atom $$A$$ is $$1s^2 2s^2 2p^6 3s^2p^6 3d^{10} 4s^2 4p^3$$. The chemistry of $$A$$ is therefore likely to be similar to that of 

Electron affinity is the 

In comparison with akali metals, the electron affinity of halogen is 

Nitrogen has lower electron affinity than its preceding element carbon because 

An element has the electronic configuration $$1s^22s^2 2p^6 3s^2 3p^6 3d^5 4s^1$$. It is a 

The most important active step in the development of periodic table was taken by

Last element of group $$IV$$ is found to be

Which metal has $$2$$ electrons in the outermost orbit