[kimi85]

1. Arrange the species in increasing ionization potential: Na, Mg, and Al
the correct answer is Na < Al < Mg

I don't how is that so.

2. How many electrons can be placed in the shell with n= 4 before the first electron enters the shell with n=5?
the correct answer is 46, but I don't don't know how to get that.

Thank you very much to anyone who can help.

[macman104]

1. Arrange the species in increasing ionization potential: Na, Mg, and Al
the correct answer is Na < Al < Mg

I don't how is that so.

Ionization potential is the energy it takes to remove an electron, yes?  So, think about this in terms of electron shells.  How many electrons are in each of those atoms outermost shells?  Keep in mind that if you are removing an electron that leaves the atom with a noble gas configuration (having the same number of electrons as a noble gas), this will be a more favorable removal.  Explore the electron configurations of these atoms, and then see what configurations are left after you remove an electron.  Write those out here if it still isn't clicking.

[kimi85]

thank you very much.