Changes Around Us for Class 6

Changes Around Us: Introduction

Changes are around us - nature is always changing. Some changes happen slowly, like how trees grow or mountains form. Other changes happen quickly, like after a storm or when animals move. These changes happen because of the weather, animals, plants, and humans. All these changes help nature grow and stay balanced. Understanding these changes helps us appreciate the world around us.

Why do changes happen?

Changes happen in nature for many reasons. The weather, like rain or wind, can change how plants grow. Animals can also cause changes, like when they spread seeds. Sometimes, humans cause changes by building things or cutting down trees. Some changes happen slowly, like mountains forming over many years, while others happen quickly, like after a storm. All these changes help nature grow and change.

Changes can be caused by the following:

 

Types of Changes

Several types of changes can happen:

1. Physical Changes: Changes that do not change the chemical make-up of a substance (example: Water is heated to steam).

2. Chemical Changes: Changes that form new substances (example: Rusting of iron).
   
   

Physical and Chemical Changes

What Are Physical Changes?

State changes are changes that do not affect a substance's chemical composition. Other examples are shape or state changes (melting, freezing, etc.).

Characteristics of Physical Changes:

• No new substances are formed.
• Usually temporary.

Example: An ice cube melts and becomes water and can freeze again to form back into ice.

What Are Chemical Changes?

Chemical change is a process that involves one or more substances being transformed into new substances.

Characteristics of Chemical Changes

• New substances are created.
• Often irreversible.

Example: When you add baking soda to vinegar, a chemical reaction takes place, and carbon dioxide gas is produced.

Things you have learned!

• Change in Nature: Nature changes all the time, from slow changes like tree growth to quick ones like storms.

• Why Changes Happen: Changes happen due to weather, animals, plants, and humans.

• Types of Changes: There are physical changes (no new substances) and chemical changes (new substances are formed).

• Examples of Changes:

  • Melting (Physical): Chocolate melts when heated.

  • Dissolving (Physical): Honey mixes with water.

  • Squeezing (Physical): Toothpaste comes out of the tube.

  • Aging (Chemical): Humans grow older.