3.3.3 WHAT IS AN ION?

Description

Quick Overview

This section discusses the concept of ions in compounds formed from metals and non-metals, expounding on the terms anions, cations, and polyatomic ions.

Standard

The section explains that compounds made of metals and non-metals contain charged species known as ions, which can be monoatomic or polyatomic. It also introduces key terms such as anions, cations, and the role of valency in forming chemical compounds.

Detailed

HATISANION

In this section, we explore the concept of ions as key components of compounds formed from metals and non-metals. Ions are charged particles that can consist of a single atom or a group of atoms, and they play a crucial role in chemistry. The section outlines the distinction between negatively charged ions, known as anions, and positively charged ions, referred to as cations.

The discussion further extends to polyatomic ions, which are groups of atoms that carry a net charge and are significant in various chemical reactions. The example of sodium chloride (NaCl) is highlighted, illustrating how it is composed of sodium ions (Na+) and chloride ions (Cl-). Furthermore, it introduces the concept of valency, which indicates the combining power of an element and is crucial for understanding how ions form compounds. This foundational knowledge sets the stage for deeper investigations into chemical reactions and compounds in subsequent sections.

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Key Concepts

  • Ions: Charged particles essential in forming compounds.

  • Cations: Positively charged ions.

  • Anions: Negatively charged ions.

  • Polyatomic Ions: Combinations of atoms that carry a charge.

  • Valency: The capacity of an element to combine with others.

Memory Aids

🎵 Rhymes Time

  • Cations smile bright, they're positive light; Anions are sad, for they've got a negative plight.

📖 Fascinating Stories

  • In a kingdom, the positive ions (cations) always teamed up with the negative ions (anions) to create strong compounds, creating harmony in their chemical kingdom.

🧠 Other Memory Gems

  • Remember the phrase: 'Cations are Cats on Tops' (for positive) and 'Anions are Ants on the Ground' (for negative).

🎯 Super Acronyms

Think 'CAN' - Cation (positive), Anion (negative).

Examples

  • Sodium chloride (NaCl) consists of sodium cations (Na+) and chloride anions (Cl-).

  • Calcium hydroxide (Ca(OH)₂) contains two hydroxide ions (OH-) combined with one calcium ion (Ca²+).

Glossary of Terms

  • Term: Ion

    Definition:

    A charged particle that can be either positively or negatively charged.

  • Term: Cation

    Definition:

    A positively charged ion.

  • Term: Anion

    Definition:

    A negatively charged ion.

  • Term: Polyatomic Ion

    Definition:

    An ion composed of two or more atoms that carry a net charge.

  • Term: Valency

    Definition:

    The combining power of an element, indicating how many electrons an atom can gain, lose, or share.