1.d. Students know how to use the periodic table to determine the number of electrons available for bonding.

Valence electrons are the electrons that are found in the outermost shell of an atom. Valence electrons participate in bonds (can move from one atom to another). Review…

Ions 11P 11N 17P 18N TaT “Take my electron! I’m an Alkali Metal!” TaT “Give me your electron! I’m a Halogen!” + -

11P 11N 17P 18N + -

Remember….Protons are positive and electrons are negative In neutral atoms (atoms with no charge) the protons and electrons are equal to one another When electrons are lost or gained – the amount of electrons become increased or decreased creating an electric charge

METALS Left LOSE e- How to determine charges on ions? Metals LOSE electrons and will become positively charged. Nonmetals GAIN electrons and will become negatively charged. NONMETALS Right GAIN e-

Alkali Metals Group 1 Alkali metals have 1 valence electron. When their one electron is given away they become a +1 charge (positive charge by 1).

Alkaline Earth Metals Group 2 Alkaline Earth metals have 2 valence electrons. When their two electrons are given away they become a +2 charge (positive charge by 2).

Have 3 valence electrons. If these elements lose 3 electrons, they become a +3 charge. The Boron Family Group 13 +3

Can gain, lose, or share four electrons when reacting with other elements If an element gains 4 electrons will become -4 charge. If an element loses 4 electrons will become a +4 charge. Carbon is the only nonmetal element in the group. The Carbon Family Group 14

Will gain or share 3 electrons. Nitrogen and Phosphorus are the 2 nonmetals in this group. Arsenic and Antimony are semimetals and Bismuth is a metal. All elements in this group, except Bismuth, will gain 3 electrons and become a -3 charge. Bismuth loses electrons. The Nitrogen Family Group 15

Will gain or share 2 electrons when reacting with other elements. When these elements gain 2 electrons, they become a -2 charge. The Oxygen Family Group 16

The Halogens and Ions The Halogens are nonmetals and they gain electrons. They have 7 valence electrons and need to gain 1. When they gain 1 electron, they become a -1 charge (negative charge by 1).

They don’t form ions. DUH!!!! They have no electrons to lose or gain. They are stable! The Noble Gases and Ions NO BONDS…..FULL OUTER SHELLS!

LOSEGain Nonmetals Also Like to Share Electrons Either

Oxidation Number Charge of an atom once it has gained or lost electrons to become stable

Transition Metals Remember…the transition elements are variable. They can have multiple oxidation numbers. This means they can lose varying amounts of electrons…creating different charges.

Cation = positively charged ion (metals form cations Anions = negatively charged ion (nonmetals form anions) Cations and Anions

WHEN REMOVING ELECTRONS THE RESULTING CHARGE IS POSITIVE Neutral No Charge 1+

WHEN ADDING ELECTRONS THE RESULTING CHARGE IS NEGATIVE Neutral No charge 3-

An atom with positive or negative charge is called an drum roll ION

Atoms without charge are called ATOMS Atoms with positive or negative charge are called IONS

Notice that ONLY the number of e - changes The number of protons in an Atom NEVER changes (Only electrons are added or subtracted)

Ions make up the salt you put on your eggs in the morning Ions are required for your brain to function (ions allow you to see and understand this presentation) Ions are an essential ingredient in soap Ions are required for cellular respiration Ions make up acids and bases Ions keep your blood functioning