i've studied that if given energy,electrons can jump orbits.so if i give energy to an atom with config. 2,8,8 ,will it become 2,7,9?if yes will its valency change?

 

thanks.

 

 

The excitation can be to even higher states than the p–d transition you describe, depending on the energy added. But the excitation is relatively brief, and the atom will de-excite back to the ground state — the odds of undergoing a reaction in the excited state are small, and that's a much more advanced concept (photoassisted reactions)