This chapter explains that we use a wide variety of materials in our daily life such as wood, plastic, metal, glass, rubber, paper, cotton, and wool. These materials differ in their properties, including appearance (shiny or dull), hardness (hard or soft), solubility (soluble or insoluble in water), transparency (transparent, translucent, or opaque), floatation (floating or sinking in water), and conduction of heat and electricity. Metals are good conductors, while wood, rubber, and plastic act as insulators. The chapter highlights that materials are selected based on their properties and the purpose they serve, such as glass for windows, metal for utensils, and plastic for bottles. It also emphasizes the importance of the proper use and recycling of materials to reduce waste and protect the environment.
Key Points
We use different materials in daily life – wood, plastic, metal, glass, rubber, paper, cotton, wool, etc.
Materials differ in properties such as:
– Appearance: shiny (metals) or dull (wood, clay).
– Hardness: hard (iron, stone) or soft (cotton, rubber).
– Solubility: some substances dissolve in water (salt, sugar) while others do not (sand, oil).
– Transparency: transparent (glass, water), translucent (butter paper), opaque (wood, metal).
– Floatation: some materials float (wood, plastic) while others sink (stone, iron).
– Conduction: metals conduct heat and electricity; wood, rubber, and plastic do not.
Materials are chosen based on their properties and the purpose they serve (example: glass for windows, metal for utensils, plastic for bottles).
Proper use and recycling of materials reduces waste and protects the environment.
👉 👉Every material has unique properties. By choosing the right material for the right purpose and reusing or recycling them, we can live wisely and care for nature.