Question

When we take out electrons from a particular atom then energy is absorbed or emitted?

Answer 1

Here, energy is absorbed in the because it actually requires energy to add an electron to an electropositive atom which has an extra shell of electrons which makes it unstable. To add another electron we would have to overcome the repulsions due the already present electrons and hence energy would have to be supplied rather than it being released.

Energy isn't always released when an electron is added to an atom. It depends on the kind of atom you are adding the electron to. 

Energy is released if the electronegative atom attains a more stable state by accepting the electron (by say attaining a octet configuration in the valence shell). Stable states have less energy when compared to other states and this difference in energy is released when an atom accepts an electron.