Conquering Chemistry help (1 Viewer)

[kittyful]

Theres this question in the conquering chemistry text book pg 87 prelim

and it says

Which of the following species contain the same number of electrons?
O^2- , F^-, Ne Al^3+
Oxygen, Fluorine, Neon and Aluminum
and the answer says all of them
How is it that all of them have the same electrons? or is it a typo in the back?

 

[Aquawhite]

You need to check the periodic table to see where they are and adjust their position in each column for the adjusted ionisation. Since protons = electrons, the column test will work and you will find that they all end up in the same spot that Neon is in.

 

[Amogh]

That is right
Oxygen's configuration is 2,6
Oxygen^2- has a configuration of 2, 8
So O^2- (an Oxygen ion) has 10 electrons

Similarly Fluorine's configuration is 2,7
but F^-1 has a configuration of 2,8 (i.e. 10 electrons)

Neon (the element) has an electronic configuration of 2,8 (i.e. 10 electrons)

Aluminum (the element) has a configuration of 2,8,3
But the Aluminum ion (Al^-3) has a configuration of 2,8 (i.e. 10 electrons)

As you can see, all of these species have 2 shells (K, L) and an octet.

 

[kittyful]

oh i get it now haha.. thankss

 

[t00l]

just a matter of referencing periodic table

btw, what edition of the textbook are u using? mines 3rd edition and its really compact but not much info here

 

[mioumiou]

just a matter of referencing periodic table

btw, what edition of the textbook are u using? mines 3rd edition and its really compact but not much info here

How come yours is in third edition?
I think most of us use the 4th edition.