9.1: Naming IonsAni Latchinian

Quarter 4 project

Monatomic Ions

Monatomic ions consist of a single atom with a positive or negative charge resulting from the loss or gain of one or more valence electrons.

Cations

Cations are positively charged ions.

When the metals in Groups 1A, 2A, 3A lose electrons, they form cations with positive charges equal to their group

For Example: Potassium (K) is in group 1A, having a 1+ charge when forming into a cation

Magnesium (Mg) is in group 2A, having a 2+ charge when forming into a cation Aluminium (Al) is in group 3A, having a 3+ charge when forming into a cation

Anions

Anions are negatively charged ions. Nonmetals tend to gain electrons to

form anions, so the charge of a nonmetallic ion is negative.

The charge of any ion of a Group A nonmetal (5A, 6A, 7A) is determined by subtracting 8 from the group number.

Anions (continued)

For example:Fluorine is in Group 7A that forms a 1- charge (7- 8=

-1)Sulfur is in Group 6A that forms a 2- charge (6- 8 = -

2)Nitrogen is in Group 5A that forms a 3- charge (5-8=-

3)

When these elements form into anions, there names change. The stem of the element name stays and the end changes to –ide.

Transition Metals

Many of the transition metals (Group 1B-8B) form more than one cation with different ionic charges and some have only one.

The charges of the cations of many transition metal ions must be determines from the number of electrons lost.

For example: Iron (transition metal) forms two types of cations- (two electrons

lost) which is named iron(II) and is read *iron two ion* & (three electrons lost) which is named iron(III) and is read *iron three ion*

Silver another transition metal only has one ionic charge, so its name as a cation wont have a Roman numeral it would just be

The Roman numeral represents the amount of charge on the ion.

Polyatomic Ions Polyatomic ions are composed of more than one atom. The names of most polyatomic anions end in –ite or –ate. They can either be cation or anion