Introduction to Atoms, Elements, and the Periodic Table

Posted on Oct 7, 2024 in Chemistry

Theoretical Concepts

1. Simple and Compound Substances

Simple substances are made up of only one type of atom, like oxygen (O2) or gold (Au).

Compound substances consist of two or more elements chemically combined in fixed proportions. For example, water (H2O) is a compound composed of hydrogen and oxygen.

2. Atoms, Chemical Elements, and Subatomic Particles

Atoms are the basic building blocks of matter.

Chemical elements are substances made up of only one type of atom.

Subatomic particles include electrons, protons, and neutrons.

3. Subatomic Particles: Electron, Neutron, Proton

Electrons have a negative charge and orbit the nucleus of an atom.

Neutrons have no charge and are found in the nucleus.

Protons have a positive charge and are also found in the nucleus.

4. History of Atomic Models

This section covers the evolution of our understanding of atomic structure, from early models like Dalton’s billiard ball model to modern models like the quantum mechanical model.

5. Mass Number, Atomic Number, Isotope, Ion, Anion, Cation

Mass number is the total number of protons and neutrons in an atom’s nucleus.

Atomic number is the number of protons in an atom’s nucleus.

Isotopes are atoms of the same element with different numbers of neutrons.

Ions are atoms or molecules that have gained or lost electrons, resulting in a net electrical charge. Anions are negatively charged ions, while cations are positively charged ions.

6. Introduction to the Periodic Table

This section covers the organization of chemical elements based on their atomic number, electron configuration, and recurring chemical properties.

7. Chemical Bonds: Molecules and Crystals

Chemical bonds are the forces that hold atoms together in molecules or crystals. This section may cover covalent bonds (sharing electrons) in molecules and ionic bonds (attraction between oppositely charged ions) in crystals.

8. Symbols and Names of Chemical Elements (English and Spanish)

This section involves learning the chemical symbols and names of various elements in both English and Spanish.

Practical Applications

Each activity involves applying the theoretical concepts in a hands-on manner.

1. Classification of Simple and Compound Substances
  • Simple substances consist of only one type of atom, such as oxygen (O2) or gold (Au).
  • Compound substances consist of two or more different types of atoms chemically bonded together, such as water (H2O) or carbon dioxide (CO2).
2. Calculation of Number of Particles
  • To calculate the number of particles (electrons, protons, and neutrons) knowing Z (atomic number) and A (mass number):
  • Number of protons (Z) = Atomic number (Z)
  • Number of neutrons (N) = Mass number (A) – Atomic number (Z)
  • Number of electrons is equal to the number of protons in a neutral atom.
3. Drawing an Atom
  • Represent the nucleus containing protons and neutrons at the center, surrounded by electron shells or energy levels.
4. Calculation of Charge and Mass of an Atom
  • The charge of an atom is determined by the balance between the number of protons (positive charge) and electrons (negative charge).
  • The mass of an atom is determined by the sum of the masses of its protons, neutrons, and electrons.
5. Metals or Non-Metals
  • Metals typically exhibit metallic properties such as luster, conductivity, and malleability. They tend to lose electrons to form positive ions.
  • Non-metals usually have properties opposite to metals, such as being dull, poor conductors, and brittle. They tend to gain or share electrons to form negative ions.
6. Classification of Atom, Molecule, or Crystal
  • An atom is the basic unit of a chemical element, consisting of a nucleus surrounded by one or more electrons.
  • A molecule is a group of two or more atoms held together by chemical bonds.
  • A crystal is a solid material whose atoms, molecules, or ions are arranged in a highly ordered, repeating pattern extending in all three spatial dimensions.