why do ionization energies increase from left to right across any period?

Answer 1

The usual answer that text books give is that you are increasing the number of protrons (which attract the electrons) without increasing the radius of the electron orbitals or increasing the shielding due to more intermediatary electron orbitals.

Answer 2

as we go from left to right in a period the electrons and protons are increasing as the atomic number increases. but the electron that are added to the same orbit as we go from left to right in any period. so the total attraction towards the nucleus will increase which results in SHIELDING EFFECT, so there is shrinkage in the size of atom. that is there is more attracion between the electrons and nucleus.now I.E is the amount of energy required to remove the electron from an atom. so as discussed earlier as ther will be more attraction toward nucleus it will require more energy to remove it.

for eg if we take Na( Z=11) and Al(Z=13). they both will be 3rd orbit as there outermost valence orbit. but sodium will have only one elctron in its outermost orbit while Al will have 3 electros. in its 3rd orbit. so the attraction of valence electrons of al will be higher than that of sodium and so its I.E will also be more. if we consider chlorine ( Z=17) it will have 7 electrons in its 3rd orbit so it will require more higher energy to remove electron from itself compared to Na and Al. everthough they all are in the same period.

Answer 3

the version is that for the time of oxygen the electron being bumped off is one from the 2p x 2 (2p as unfavorable to an s). The repulsion between the two electrons in the comparable orbital potential that the electron is extra handy to do away with then in the event that they weren't.

Answer 4

More protons attracting more electrons..Think of it in terms of magnets...2 magnets will attract but weakly..add more magnets the attraction becomes stronger