November 5th, 2015

• Check Ionic Radii ws

• Understand Ionization energy trend

• Understand Electron Affinity trend

Point of Today:

1. Understand trends:

Ionization Energy

Ionization Energy: The amount of energy it takes to remove an

electron

More energy required to remove electrons from smaller atoms.

(Primary factor)

Hi g

h i o

niza

t ion

Ene

r gy

Left to Right, it takes more energy to remove electrons;

nucleus has more control.

(Secondary factor)

High Ionization Energy

e-

e-

Low energ

y to re

move

High energ

y to re

move

Sodium - Na

Francium - Fr

10 20 30 40

An atom with a large atomic size will have smaller ionization energy!

High Ionization Energy

Easiest

elect

ron to re

move

Hardest

Electro

n to re

move

Hi g

h i o

niza

t ion

Ene

r gy

Which has a larger Ionization energy…?

1. Sr or I

2. Br or Kr

It is easy to remove the first electron from Aluminum.

There are now more protons than electrons and the nucleus pulls those

remaining electrons tight. Therefore, it is hard to remove the next electron.

Now the nucleus has even a stronger hold on this electron.

It is now almost impossible to remove another electron. We have

now reached the electron configuration of a noble gas!

First Ionization Energy

• A metal is characterized by a low first ionization energy.

• An element with a high first ionization energy is a nonmetal.

Assignment

• Complete Ionization energy ws we will check in 10 minutes.