Halogens have electron affinity
a) exothermic
b) endothermic
c) positive
d) zero

Determine the  wavelength of light emitted when an electron  in an li2+ ion  makes a transition from an orbital with n  =  6 to an orbital with n  = 5.

Idont know. if you want an answer you need to give us some context dude.

Answerelement;