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Lesson 2FORMATION OF IONSG11 – Maxwell – Pasteur- Faraday

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z Monatomic Ions

Elements Symbol Ion Name Ion Formula

1. Sodium

2. Bromine

3. Magnesium

4. Chlorine

5. Oxygen

6. Boron

7. Lithium

8. Potassium

9. Phosphorus

10. Aluminum

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IONS

- an atom or group of atoms that has charge due to losing or

gaining one or more electrons.

- classification of ions

CLASSIFICATION EXAMPLES

By Composition

Monatomic(1 atom) Fe²⁺, Li⁺, Mg²⁺, N³⁻

Polyatomic(more than 1 atom) SO₄²⁻, ClO₃⁻, CO₃²⁻

By kind of charge

Cation (positive-lose) Na⁺, Mg²⁺, Al³⁺

Anion (negative-gain) Cl⁻, O²⁻, I⁻

By magnitude of charge

Monovalent (+1 or -1) Li⁺, K⁺, OH⁻

Divalent (+2 or -2) Ca²⁺, SO₄²⁻, Cu²⁺

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Symbols and names for simple ions

Group Element Name of Ion Symbol for Ion

IA Hydrogen

Lithium

Sodium

Potassium

Hydrogen ion

Lithium ion

Sodium ion

Potassium ion

H⁺Li⁺Na⁺K⁺

IIA Magnesium

Calcium

Magnesium ion

Calcium ion

Mg²⁺Ca²⁺

IIIA Aluminum Aluminum ion Alᴲ⁺

VA Nitrogen Nitride ion Nᴲ¯

VIA Oxygen

Sulfur

Oxide ion

Sulfide ion

O²¯S²¯

VIIA Fluorine

Chlorine

Bromine

Iodine

Fluoride ion

Chloride ion

Bromide ion

Iodide ion

F⁻Cl⁻Br⁻I⁻

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Valence Electrons of Atoms and Corresponding Oxidation No.

Valence Electrons

(electrons in the outermost shell)

Oxidation Number

1

2

3

4

5

6

7

8

1⁺

2⁺

3⁺

±4

3¯

2¯

1¯

0

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Nomenclature of Ions

▪ MONATOMIC METALS AND NONMETAL

> metals are named as is while nonmetals end in the suffix

-ide. This means that the last syllable of the name of the

nonmetal is dropped and the suffix –ide is attached.

METALS NONMETALS

Calcium ion - Ca²⁺ Sulfide ion - S²¯

Aluminum ion - Alᴲ⁺ Chloride ion - Cl¯

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The Monatomic Representative IonsIA IIA IIIA IVA VA VIA VIIA

H⁺ Be²⁺ Alᴲ⁺ C Nᴲ¯ O²¯ F¯

Li⁺ Mg²⁺ Pᴲ¯ S²¯ Cl¯

Na⁺ Ca²⁺ Se²¯ Br¯

K⁺ Sr²⁺ Te²¯ I¯

Rb⁺ Ba²⁺

Cs⁺

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▪ METALS WITH VARIABLE OXIDATION NOS. (TRANSITION)

> some metal ions have variable oxidation numbers or exhibit

more than one oxidation number.

> in naming these ions, 2 systems are used:

a. IUPAC or STOCK

- by Albert Stock

- names metals as is and uses Roman Numerals in

parenthesis affixed after the name to indicate

the oxidation state of the metal

b. TRADITIONAL or CLASSICAL

- uses Latin names of the metals which end with

-ous (lower oxidation number) and –ic (higher

oxidation number).

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▪ Examples:

Transition Metals IUPAC/STOCK TRADITIONAL/CLASSICAL

1. Fe²⁺Feᴲ⁺

Iron (II)

Iron (III)

Ferrous

Ferric

2. Cu⁺Cu²⁺

Cupper (I)

Cupper (II)

Cuprous

Cupric

3. Hg⁺Hg²⁺

Mercury (I)

Mercury (II)

Mercurous

Mercuric

4. Mn²⁺Mn⁴⁺

Manganese (II)

Manganese (IV)

Manganous

Manganic

5. Pb²⁺Pb⁴⁺

Lead (II)

Lead (IV)

Plumbous

Plumbic

z▪ NONMETALS CAN ALSO FORM POLYATOMIC IONS WITH OXYGEN

> contain oxoanions or negative ions which consist of the

element oxygen with other nonmetals.

> the anion with LESSER OXYGEN atoms ends with –ite while

with MORE OXYGEN atoms ends with –ate.

> Examples:

SO₃²¯ - sulfite

SO₄²¯ - sulfate

NO₂¯ - nitrite

NO₃¯ - nitrate

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▪ HALOGENS CAN FORM 4 DIFFERENT POLYATOMIC IONS WITH

OXYGEN. Each ion is named differently depending on the number of

oxygen atoms present.

▪ (1 O=hypo, 2 O=-ite, 3 O=-ate, 4 O=per)

▪ Examples:

ClO¯ - hypochlorite

ClO₂¯ - chlorite

ClO₃¯ - chlorate

ClO₄¯ - perchlorate

IO¯ - hypoiodite

IO₂¹¯ - iodite

IO₃¹¯ - iodate

IO₄¹¯ - periodate

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▪ WHEN OXOANIONS COMBINE WITH METALS, THE NAME

OF THE METAL IS WRITTEN FIRST FOLLOWED BY THE

NAME OF THE OXOANION.

▪ Examples:

K₂SO₄ - potassium sulfate

K₂SO₃ - potassium sulfite

NaNO₃ - sodium nitrate

NaNO - sodium nitrite

KClO₄ - potassium perchlorate

Ca(BrO₄)₂ - calcium perbromate

Ca(ClO)₂ - calcium hypochlorite

Al(BrO)₃ - aluminum hypobromite

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▪ TERNARY POLYATOMIC IONS (consisting of 3 different

elements) MAYBE FORMED BY THE ADDITION OF

HYDROGEN ATOMS TO BINARY POLYATOMIC IONS

(consisting of 2 different elements).

a. If there is only one type of ternary ion formed, a prefix bi-

is added to indicate the presence of hydrogen in the

chemical formula.

Ex: CO₃²¯ carbonate → HCO₃¯ bicarbonate

b. If there are several types of ions formed with hydrogen,

Greek prefixes are used to indicate the no. of hydrogen

atoms present in the ion.

Ex: PO₄ᴲ¯ phosphate → HPO₄²¯ hydrogen phosphate

→ H₂PO₄¯ dihydrogen phosphate

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Seatwork 1

▪ Complete the table by writing the formula of the

compounds to be formed by each combination.

Cl¯ O²¯ NO₃¯ SO₄²¯ PO₄ᴲ¯

K⁺

Mg²⁺

Alᴲ⁺

NH₄⁺

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Seatwork 2▪ Fill up the table.

Name of

Element

IONS IUPAC/STOCK TRADITIONAL/CLASSICAL

1. Cr²⁺

Crᴲ

2. Cu⁺

Cu²

3. Co²⁺

Coᴲ⁺

4. Ni²⁺

Niᴲ⁺

5. Au⁺

Auᴲ⁺

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