History and Science: Ages and Atomic Models

Stone Age, Bronze Age, and Iron Age

• Stone Age humans used stone tools for hunting, gathering, and building.
• They relied on fire and tools for survival.
• Bronze Age saw the introduction of bronze tools and weapons, improving technology.
• Iron Age featured iron tools and weapons, leading to stronger tools and more advanced warfare.

Atomic Models

• Dalton proposed the Solid Sphere Model, where atoms were indivisible spheres.
• Thomson's Plum Pudding Model introduced the idea of subatomic particles (electrons).
• Rutherford's Gold Foil Experiment led to the Nuclear Model, recognizing the nucleus.

Subatomic Particles

• Electrons are negatively charged particles orbiting the nucleus.
• Protons are positively charged particles found in the nucleus.
• Neutrons are neutral particles located in the nucleus.

Atomic Mass

• Atomic mass is the total mass of an atom, composed of protons and neutrons.

Dmitri Mendeleev and the Periodic Table

• Mendeleev organized elements by increasing atomic mass.
• He predicted the properties of undiscovered elements.

20 Common Elements

• Hydrogen (H), Helium (He), Lithium (Li), Beryllium (Be), Boron (B), Carbon (C), Nitrogen (N), Oxygen (O), Fluorine (F), Neon (Ne), Sodium (Na), Magnesium (Mg), Aluminum (Al), Silicon (Si), Phosphorus (P), Sulfur (S), Chlorine (Cl), Argon (Ar), Potassium (K), and Calcium (Ca).

Periodic Table (PT) Information

• Atomic mass is listed below the element symbol.
• Atomic number is above the element symbol.
• Periods are horizontal rows.
• Groups are vertical columns.

Element Locations on the PT

• Metals are located on the left and center of the table.
• Nonmetals are on the right side (excluding hydrogen).
• Metalloids are along the "stair-step" line separating metals and nonmetals.
• Noble gases are in Group 18, far right column.

Determining Subatomic Particles

• Protons are equal to the atomic number.
• Electrons are equal to the number of protons.
• Neutrons are calculated by subtracting the atomic number from the atomic mass.

Scientific Advancements and History

• Scientists' observations and theories were driven by a desire to improve previous models and discover new knowledge.

Explore key developments from the Stone Age to the Iron Age, highlighting technological advancements in tool-making. Additionally, dive into atomic theories from Dalton to Mendeleev, discovering the structure and mass of atoms as well as the arrangement of the periodic table.