Basic Concepts of Chemistry

Chemistry is the study of matter and its properties.

Matter:
Anything that has mass and occupies space.

States of Matter:
Solid, Liquid, Gas

Importance:
Chemistry is used in medicine, industry, and daily life

Introduction:
Physics deals with matter and energy. Measurement is essential to understand physical quantities.

Physical Quantities:
Measurable properties such as length, mass, and time.

SI Units:
Length → meter
Mass → kilogram
Time → second

Importance:
Measurement ensures accuracy in experiments and calculations.

Definition of Set

A set is a well-defined collection of distinct objects.

Examples:

  • A = {1, 2, 3}
  • B = {a, e, i, o, u}

Types of Sets

1. Finite Set

A set having limited number of elements.
Example: {1,2,3}

2. Infinite Set

A set with unlimited elements.
Example: Natural numbers

3. Empty Set (Null Set)

A set with no elements.
Example: ∅

4. Equal Sets

Two sets having same elements.


Methods of Representation

1. Roster Form

List all elements
Example: A = {1,2,3}

2. Set Builder Form

Define property
Example: A = {x | x < 5}


Basic Operations on Sets

Union (∪)

A ∪ B = elements in A or B

Intersection (∩)

A ∩ B = common elements

Difference (−)

A − B = elements in A not in B


Venn Diagram

Used to represent sets graphically.