Bonding

Where do electrons live again? In orbitals (or clouds) around the nucleus.

What is an orbital? The area that you are most likely to find an electron.

What are the shapes of the orbitals? s - spherical p - dumbbell d – clover leaf f - too complicated

Can we draw atoms with the modern theory? Not really, we just tell what energy level they are in, which shape orbital and how many electrons are there.

What rules do I use to fill the orbitals? Aufbau’s Rule Pauli Exclusion Principle Hund Rule

What is the Aufbau Rule? You must fill the electrons in a certain order The lowest energy levels are first

How do I show an energy level? A number 1-7 Written first 2s 2 4d 8

Where do I start? You always start with the beginning of the periodic table, with the 1 st energy level

What order do I use? Follow the periodic table

What is the Pauli Exclusion Principle? Orbitals hold 2 electrons each Each shape has different numbers of electrons The two electrons in each orbital spin in opposite directions

How many of each orbital are there? s – 1 p – 3 d – 5 f - 7 spdfspdf

How do I show one orbital? A line

How do I show an electron? As an arrow

Why as an arrow? So you can show it spinning in the different directions

How many arrows per line? 2

What is Hund’s Rule? You have to spread out the electrons before you can double them up

Are the arrows and orbitals always necessary? Not in electron configurations.

What do you put instead? The number of electrons in that orbital.

So why are there only 8 valence electrons in an octet? Only the s and p orbitals are valence shells.

What is a ground state electron? An electron with its “normal” amount of energy.

What happens when an electron gets excited? It jumps energy levels and emits a photon.

What is a photon? A quanta (bundle) of light from the electromagnetic spectrum that acts like a particle.

What is this light that is emitted called? The electron emission spectrum. Each element has its very own color it emits.

What is a compound? It is 2 or more elements chemically combined together.

How do I read compounds? They tell you the elements present and how many of that element

What number is not written? 1

What do I do with parentheses? The number at the END gets distributed through the parentheses.

Examples: MgCl 2 NaC 2 H 3 O 2 Sc 3 (PO 4 ) 2

What happens to valence electrons? They are bonded to other atoms to make octets

What are the two types of bonds? Ionic and Covalent

What is an ionic bond? Made up of a cation and an anion (metal and a nonmetal)

What happens to the valence electrons? They are stolen by the non metal from the metals

Try to draw this ionic bond: SrO

Try to draw this ionic bond: Na 2 S

Try to draw this ionic bond: AlP

Try to draw this ionic bond: GaCl 3

Try to draw this ionic bond:

What is a covalent bond? Made up of two non metals

What happens to the electrons in a covalent bond? The electrons are shared between atoms to make octets

What are the properties of ionic bonds? Conduct electricity High melting points High boiling points Break along set lines Strong bonds

What are the properties of covalent bonds? Weak bonds Low melting points Low boiling points Shatter when broken Do not conduct electricity

How do I draw ionic bonds? With Lewis Dot diagrams

What do you do with them? Write the Lewis Dots, but show the transfer of electrons and charges.

How can I draw covalent bonds? Lewis dot diagrams and their shapes

How many electrons can be shared? 2, 4 or 6 electrons to have a full octet

How do I show 2 shared electrons? A line Called a single bond

What about a double bond? Sharing 4 electrons 2 lines

And a triple bond? 6 electrons 3 lines

What is a lone pair? Electrons that are in an octet, but do not bond with anything

What are the shapes of the covalent bonds? Linear Trigonal planar Tetrahedral Pyramidal Bent

What is a linear molecule? Everything is in a straight line

What is a trigonal planar molecule? Around your central atom, there are 3 items: 3 bonded sides 2 bonded sides and 1 lone pair

What is a tetrahedral molecule? There are 4 bonds on the central atom.

What is a pyramidal molecule? There is one lone pair and 3 bonded sides.

What is a bent molecule? There are 2 bonded sides and 2 lone pairs.

Do atoms always share electrons evenly? No

What is it called when they share equally? Non-polar

How do I know if I have a non-polar molecule? If the molecule has NO lone pairs on the central atom

What is it called when they do not share equally? Polar

How do I know if I have a polar molecule? If the central atom has lone pairs, it is polar.