Periodic Blocks

Chapter 6

Quick review (Stuff u should know already!!!!)

What is a valence electron?– Electrons in the highest principle energy level– What’s the principle energy level?

1, 2, 3, 4, 5…. (n)

Remember Aufbau diagram…

Sublevels

How many electrons in s?– 2

How many electrons in p?– 6

How many electrons in d?– 10

How many electrons in f?– 14

Observations???

Observations

What was the connection between period number and the elements that you were assigned?– Valence electrons?– Principle quantum number?– Sublevel?– Orbital?– Partially filled or completely filled?

Period # & Valence electrons

The energy level of the valence electrons of an element tell you the period that it will be in (the row!!!)

Remember, energy level is your principle quantum number (n)

S-Block

Groups 1a and 2a Valence electrons occupy only s-orbitals Group 1a partially filled s Group 2a completely filled s How many max electrons can an s-orbital

hold? Soooo how many groups are going to

makeup the s-block?– 2

So what sublevel do we go to after we fill an s-sublevel?

P-sublevel….

P-block

How many orbitals does the p sublevel have?– 3…remember, three lines _ _ _

Do you think we will have more or less electrons here than the s-block?– MORE!!!

Groups 3a thru 8a Why is there no p-block elements in period 1?

– Because at energy level (principal quantum #) 1, we do not have any p sublevels

How many max electrons can a p-sublevel hold? SO how many groups is the p-block going to have?

– 6

Noble gases in P-block

What do we notice about their s and p orbital???– They are completely full– So they are stable…no chemical reaction– Important later when we talk about ions….

Welcome to the D-Block!

Contains transition metals How many elements are going to reside on the D-block?

– Lots!

There are many exceptions but….– Filled outermost s-orbital of energy level n– Filled or partially filled d-orbitals of energy level n-1

What happens to the d orbitals as we move across a period? How many groups do you think are going to make up the d-

block?– Hint: How many electrons can a d-sublevel hold?– 10!!!!

F-Block elements…uh-oh….

What do we have left on the periodic table?– Lanthanide and actinide series (inner transition metals)– They fall into periods 6 and 7

Characterized by:– Filled or partially filled outer most s-orbital– Filled or partially filled 4f and 5f orbitals

Sorry guys…these electrons in the f-block do not fill in a predictable manner

How many columns are going to make up the f-block?

– Hint: How many electrons can an f-sublevel hold?– 14!!!!

So….

Now we see why the periodic table has that funny shape!

We can now also do electron notations in less tedious manner!

Tell me what happens….

To the principle energy levels as we move down a period?– Princ. E level increases

To the number of sublevels containing electrons as we move down a period?– Increases too!!!

Practice problems!!!

Periodic tables away!!! Tell me the group, period, and block of an

atom with the following electron configurations:– [Ne]3s2

– [He]2s2

– [Kr]5s24d105p5

Answers

– [Ne]3s2

Group 2a Period 3 S-block

– [He]2s2

Group 2a Period 2 S-block

– [Kr]5s24d105p5

Group 7a Period 5 p-block

More problems…

Write the electron configuration for the following elements:– The group 4b element in the fifth period?– The group 1a element in the seventh period?

Answers

– The group 4b element in the fifth period? Zirconium [Kr]5s24d2

– The group 1a element in the seventh period? Francium [Rn]7s1

REPRESENTATIVE BLOCK PARTY!!!

Make cube…how many sides is this?– 6

Side 1…Artistically symbol of element with vitals Side 2…Label the elements group Side 3…Write the element’s electron configuration Side 4…Illustrate/describe Properties of the element Side 5…Illustrate/describe Uses of element Side 6…Important compounds this element is found

in

Periodic Trends

What’s a trend