Atomic Symbols and Valence

Study Notes

Atomic Symbols and Valence of Elements

Atomic Symbols

Represented by a one- or two-letter abbreviation of the element's name
Derived from the Latin or Greek name of the element
Examples:
- Hydrogen: H
- Carbon: C
- Oxygen: O
- Aluminum: Al (from Aluminum)

Valence of Elements

Valence: the combining power of an element, i.e., the number of electrons an atom can gain, lose, or share to form bonds
Valence electrons: the outermost electrons of an atom, involved in bonding
Types of valence:
- Positive valence (oxidation number): the number of electrons lost by an atom
- Negative valence (reduction number): the number of electrons gained by an atom
Examples:
- Hydrogen: +1 (loses 1 electron)
- Oxygen: -2 (gains 2 electrons)
- Aluminum: +3 (loses 3 electrons)

Periodic Table and Valence

Elements in the same group (vertical column) have similar valence
Elements in the same period (horizontal row) exhibit a gradual change in valence from left to right
Metals tend to lose electrons (positive valence), while nonmetals tend to gain electrons (negative valence)

Valence and Chemical Bonding

Valence determines the type of bonds an element can form:
- Ionic bonds: formed between elements with large differences in valence
- Covalent bonds: formed between elements with similar valence
Valence and bonding determine the properties of compounds and molecules

Description

Test your knowledge of atomic symbols and valence of elements, including their combining power, valence electrons, and bonding properties. Learn how valence determines the type of bonds an element can form and its role in the periodic table.