This section delves into the formation of ions and the organization of the periodic table, which is crucial for understanding cations and anions in chemistry.

Ion formation occurs when atoms gain or lose electrons:

• Anions are negative ions formed when atoms gain electrons
• Cations are positive ions formed when atoms lose electrons

Example: $F$- indicates a fluorine atom that has gained an electron, becoming a negative ion $anion$. $Na$+ represents a sodium atom that has lost an electron, becoming a positive ion $cation$.

The periodic table is organized to reflect these properties:

• Group numbers indicate the number of valence electrons
• Elements in the same group have similar chemical properties

Vocabulary: Reactive metals are elements that vigorously react with other elements and water. They are typically soft and found on the left side of the periodic table.

Highlight: Non-metals, found on the right side of the periodic table, typically have low melting and boiling points. Many are liquids or gases at room temperature and pressure.

Understanding trends in the periodic table is essential for predicting reactive metals properties and periodic table arrangement.

Key trends observed in the periodic table:

• As you move down a group, the number of electron shells increases
• Larger atoms lose electrons more easily going down a group
• Larger atoms gain electrons less easily going down a group

Example: In Group 1 $Alkali Metals$, the reactivity increases as you move down the group. This is because the outer electron gets further from the nucleus, making it easier to lose.

Properties of reactive metals:

• Very low density $they float on water$
• Very soft
• Good conductors of electricity and heat

Highlight: Alkali metals are highly reactive and must be stored in oil to prevent reaction with oxygen in the air.

Reasons for increased reactivity down a group:

• Atoms get larger
• Outer electrons are further from the nucleus
• Attraction between nucleus and outer electrons weakens

Definition: Malleability is the ability of a metal to be hammered or pressed into thin sheets without breaking.

General properties of metals:

• Malleable
• Shiny surface when first cut $dulls due to reaction with oxygen$
• Relatively high melting and boiling points

Understanding these trends and properties helps in predicting the behavior of elements across the periodic table.

This page explores the trends observed in the periodic table, particularly focusing on atomic size and reactivity as you move down a group.

Definition: As you move down a group in the periodic table, the number of electron shells increases, leading to larger atoms.

The page explains the effects of increasing atomic size:

• Larger atoms lose electrons more easily
• Larger atoms gain electrons less easily

Example: The trend is illustrated using Group 1 elements $Alkali Metals$ from Lithium $Li$ to Francium $Fr$, showing how atomic size increases down the group.

The page delves into why reactivity increases as you move down a group:

• Atoms get larger
• The outer electron gets further from the nucleus
• The attraction between the nucleus and outer electron weakens

Highlight: This trend in reactivity is particularly important for understanding the behavior of reactive metals properties and periodic table arrangement.

The properties of alkali metals are also discussed:

• Very reactive $stored in oil to prevent reaction with oxygen$
• Low density $float on water$
• Soft
• Good conductors of electricity and heat

This information provides a comprehensive understanding of how atomic structure influences chemical properties and reactivity across the periodic table.

This page focuses on the distinguishing properties of metals and non-metals, which is crucial for understanding their behavior and applications in chemistry.

Definition: Metals are elements that typically have certain characteristic properties, such as being malleable, shiny, and good conductors of electricity and heat.

The page lists key properties of metals:

• Malleable $can be shaped without breaking$
• Shiny surface when freshly cut
• Good conductors of electricity and heat

Highlight: The shiny surface of metals can dull over time as they react with oxygen in the air, forming a layer of oxide.

The page also touches on the properties of non-metals, which generally have opposite characteristics to metals:

• Often brittle or gaseous at room temperature
• Poor conductors of electricity and heat
• May have dull appearances

Example: The difference in properties between metals and non-metals is illustrated by comparing elements like iron $metal$ and sulfur $non-metal$.

This information is essential for understanding the behavior of different elements in chemical reactions and their applications in various fields. It also helps in comprehending the reactive metals properties and periodic table arrangement, as the position of an element in the periodic table often correlates with its metallic or non-metallic nature.

This page delves into more advanced concepts related to atomic structure and periodic trends, building upon the foundational knowledge established in earlier sections.

Definition: Periodic trends are patterns of changes in properties of elements as you move across a period or down a group in the periodic table.

The page explores several important periodic trends:

1. Atomic Radius: Decreases across a period $left to right$ Increases down a group
2. Ionization Energy: Increases across a period Decreases down a group
3. Electronegativity: Increases across a period Decreases down a group

Example: The trend in atomic radius is explained using elements from Period 2 $Li to Ne$ and Group 1 $Li to Fr$.

The page also introduces the concept of electron affinity and its trends across the periodic table.

Highlight: Understanding these trends is crucial for predicting the chemical behavior of elements and their compounds.

The relationship between an element's position in the periodic table and its chemical properties is emphasized, reinforcing the importance of atomic structure and periodic table study notes for a comprehensive understanding of chemistry.

Vocabulary:

• Ionization Energy: The energy required to remove an electron from an atom
• Electronegativity: The ability of an atom to attract electrons in a chemical bond

This advanced information provides a deeper insight into the principles governing reactive metals properties and periodic table arrangement, as well as the factors influencing cations and anions in chemistry.

The atomic structure forms the foundation of understanding cations and anions in chemistry. Atoms are primarily composed of empty space surrounding a nucleus.

Key points about atomic structure:

• The nucleus contains protons and neutrons
• Electrons orbit the nucleus in shells
• The number of protons equals the number of electrons in a neutral atom
• The atomic mass is the sum of protons and neutrons

Definition: An ion is an atom with an electric charge due to the gain or loss of electrons.

Example: Beryllium $Be$ has 4 protons and electrons, with 5 neutrons. Carbon $C$ has 6 protons and electrons, with 6 neutrons.

The periodic table organizes elements based on their atomic structure, with elements arranged in groups according to their properties.

Highlight: Electron shells can hold specific numbers of electrons: 2 in the first shell, 8 in the second, and 8 in the third.