How Can The Bohr Model Of The Atomic Structure Be Used Toexplain The Reactivity Of Alkali Metals?

Basically, the higher energy shell that the outer electron is situated in, the less electrostatic forces are acting upon it from the nucleus (because the outer electron is further away as it moves up energy shells, so there are less forces attracting it to the nucleus).  This means that the electron has more energy to form bonds with other atoms: Which makes it more reactive. 

With the bohr diagram one cans see how many available electrons can be "traded" by the element thus showing its level of reactivity. 

One electron is present in the outermost orbit, so this is most feebly
attracted and hence can easily be removed. I guess dats what meks em
reactive

Oh my god this is Well easy

Oi you guest, your not even funny, you dirty sod!

Oh, I already know all of that. But what does gaining energy have anything to do with losing the valence atom?