# Materials Used in Daily Life - Grade 10 (SEE) Science
## Complete Chapter Notes with All Exercises - NEB Curriculum
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## 🎯 Chapter Overview
**Look around you! The chair you're sitting on, the glass you drink from, the clothes you wear—all are made of fascinating materials.** This chapter, "Materials Used in Daily Life," uncovers the science behind everyday objects. These notes are your ultimate guide, making complex topics like glass, cement, plastics, and soaps incredibly simple and easy to remember.
**This is a high-scoring and practical chapter for your SEE exam.** We'll explore how these materials are made, what makes them special, and why choosing the right material for a job is so important. With clear explanations, helpful tables, and solutions to every single textbook exercise, you'll be able to see the world around you with a chemist's eye!
**Weightage:** 8-10 marks in SEE examination
**Time Required:** 15-20 periods
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## 📚 Learning Objectives
After studying this chapter, you will be able to:
- Identify the raw materials and manufacturing processes for glass, cement, ceramics, and plastics.
- Differentiate between various types of glass, plastics, and fertilizers.
- Explain the chemistry of soaps and detergents and how they clean.
- Understand the role of fertilizers and insecticides in agriculture and their environmental impact.
- Explain the importance of responsible use and management of man-made materials.
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## 🧊 1. GLASS: The Supercooled Liquid
Glass is a hard, brittle, transparent, and **amorphous** (non-crystalline) solid. Interestingly, it's often called a **supercooled liquid** because its molecules are arranged randomly, like a liquid, rather than in a fixed pattern like a true solid. This is why very old window panes are sometimes found to be thicker at the bottom.

**Common Raw Materials:**
- **Silica** or Sand ($SiO_2$) - The main ingredient.
- **Sodium Carbonate** ($Na_2CO_3$) or Soda Ash - Lowers the melting point of silica.
- **Calcium Carbonate** ($CaCO_3$) or Limestone - Makes the glass insoluble in water.

### Types of Glass

| Type of Glass | Key Raw Materials | Properties | Main Uses |
|---|---|---|---|
| **Soft Glass** (Soda-lime) | Silica + Soda Ash + Limestone | Low melting point, cheap, not heat-resistant. | Window panes, bottles, mirrors, light bulbs. |
| **Hard Glass** (Potash-lime) | Silica + **Potassium Carbonate** + Limestone | High melting point, durable, resistant to chemicals. | Laboratory apparatus (beakers, flasks). |
| **Pyrex Glass** (Borosilicate) | Silica + Soda Ash + **Boric Oxide** ($B_2O_3$) | Very heat resistant, low thermal expansion (doesn't crack on heating).| Lab equipment, ovenware, cookware. |
| **Lead Crystal Glass** (Flint)| Silica + **Potassium Carbonate** + **Lead Oxide ($PbO$)** | Heavy, shiny, high refractive index (sparkles). | High-quality lenses, prisms, decorative items. |
| **Water Glass** (Sodium Silicate)| Silica + Sodium Carbonate | **Soluble in water**, fireproof. | Fireproofing materials, adhesives, silica garden. |
| **Quartz Glass** (Silica Glass) | Pure Silica ($SiO_2$) | Very high melting point (~1600°C), transparent to UV light. | Lenses for scientific instruments, optical fibers. |

### Fun Fact: Coloring Glass
Tiny amounts of metal oxides are added to glass to give it color:
- **Cobalt Oxide ($CoO$)** $\rightarrow$ Blue Glass 💙
- **Copper Oxide ($Cu_2O$)** $\rightarrow$ Red Glass ❤️
- **Nickel Oxide ($NiO$)** $\rightarrow$ Black/Brown Glass 🖤
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## 🧱 2. CEMENT & CONCRETE: The Binder of Our World
**Cement** is a fine, grey powder made from limestone and clay. When mixed with water, it sets into a hard mass. This setting is a chemical process called **hydration** of calcium silicates and calcium aluminates.

- **Manufacturing:**
    1.  Limestone ($CaCO_3$) and clay are crushed and heated in a kiln to about 1500°C.
    2.  This forms small, hard balls called **cement clinker**.
    3.  The clinker is cooled and ground into a fine powder with 2-3% **gypsum** ($CaSO_4 \cdot 2H_2O$).

- **Why is Gypsum added?** **SUPER IMPORTANT!** Gypsum is added to **slow down the setting time of cement**. This gives workers more time to mix, transport, and apply it before it hardens, which also helps it achieve greater strength.

### Cement Mixtures
- **Mortar:** Cement + Sand + Water. Used for plastering and joining bricks.
- **Concrete:** Cement + Sand + Gravel (small stones) + Water. Used for building floors, roofs, and pillars.
- **RCC (Reinforced Cement Concrete):** Concrete with an internal framework of iron rods. The iron provides tensile strength, making RCC incredibly strong and suitable for bridges, dams, and large buildings. 

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##🏺 3. CERAMICS: The Art of Clay
**Ceramics** are materials made from special clay called **kaolin** (a pure, white clay), which is then hardened by fire.

- **Process:**
    1.  Clay is mixed with water to make it pliable.
    2.  It's molded into the desired shape (e.g., a cup or tile).
    3.  It's dried and then fired in a kiln at high temperatures.
    4.  A process called **glazing** is often done, where a glassy coating is applied to make the ceramic waterproof, smooth, and decorative.

- **Properties:** Hard, brittle, excellent insulators of heat and electricity, resistant to chemicals.
- **Uses:** Crockery (cups, plates), tiles, bricks, electrical insulators.

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## 🧴 4. PLASTICS & FIBERS: The Marvels of Polymerization
**Plastics** are synthetic materials made of large molecules called **polymers**. Polymers are long chains made by linking many small repeating units called **monomers**.
**Monomer + Monomer + ... $\rightarrow$ Polymer** (This process is called Polymerization)

### Thermoplastics vs. Thermosetting Plastics
**Analogy:** Thermoplastics are like **butter**—you can melt it and solidify it again and again. Thermosetting plastics are like a **cake**—once you bake it, you can't un-bake it!

| Feature | Thermoplastics | Thermosetting Plastics |
|---|---|---|
| **Effect of Heat** | Soften on heating, can be remolded. | Do not soften on heating; they char and harden permanently. |
| **Examples** | **PVC** (Polyvinyl Chloride) - pipes. **Polythene** - plastic bags. | **Bakelite** - electrical switches, cooker handles. **Melamine** - unbreakable dinnerware. |
| **Raw Materials**| Ethene for Polythene; Vinyl Chloride for PVC. | **Phenol (Carbolic Acid) + Formaldehyde** for Bakelite. |

### Fibers
Fibers are thin, thread-like structures.
- **Natural Fibers:** Obtained from plants and animals (e.g., Cotton, Silk, Wool).
- **Synthetic Fibers:** Man-made polymers (e.g., Nylon, Orlan, Rayon).
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##🧼 5. SOAPS & DETERGENTS: The Chemistry of Cleaning

### Soap
- **What is it?** A sodium or potassium salt of a long-chain fatty acid. (e.g., Sodium Stearate).
- **Raw Materials:** Animal fat or vegetable oil + an Alkali (like NaOH).
- **Saponification:** The process of making soap by boiling fats/oils with an alkali.
  **Fat/Oil + Alkali $\xrightarrow{Heat}$ Soap + Glycerol**
- **Problem:** Soap does not work well in **hard water** as it forms insoluble scum.

### Detergent
- **What is it?** A synthetic cleansing agent made from petrochemicals (e.g., Sodium Lauryl Sulphate).
- **Advantage:** Detergents work perfectly in both **soft and hard water** because they don't form scum. They also have a stronger cleansing action.
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## 🌱 6. FERTILIZERS & INSECTICIDES: Feeding & Protecting Plants

### Fertilizers
Fertilizers are substances added to soil to supply essential nutrients for plant growth.

| Nutrients | Role in Plants | Deficiency Symptoms |
|---|---|---|
| **Nitrogen (N)** | Promotes rapid leaf and stem growth; essential for protein. | Stunted growth, **yellowing of leaves (chlorosis)**. |
| **Phosphorus (P)**| Essential for root development, flowering, and seed formation. | Poor root growth, delayed ripening of fruits. |
| **Potassium (K)**| Improves overall plant health, strong stems, disease resistance. | Weak stems, unhealthy roots and shoots. |

- **Organic Fertilizer (Compost):** Made from decayed organic matter. It's eco-friendly and improves soil structure.
- **Chemical Fertilizer:** Synthetically produced. **NPK fertilizers** are called "complete fertilizers" because they contain all three primary nutrients.

### Insecticides
Chemicals used to kill insects and pests.
- **Example:** DDT (Dichlorodiphenyl Trichloroethane).
- **Impact:** Overuse causes **chemical pollution**, harming beneficial organisms and contaminating the food chain.
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## 🌍 7. ENVIRONMENTAL IMPACT & WASTE MANAGEMENT
The production and disposal of man-made materials can cause **chemical pollution**.

### Solid Waste Management
This is the process of collecting, transporting, processing, and disposing of waste materials.
- **Biodegradable Waste:** Wastes that can be decomposed by microorganisms (e.g., food scraps, paper).
- **Non-biodegradable Waste:** Wastes that cannot be decomposed naturally (e.g., plastic, glass, metals).

**Methods of Disposal:**
- **Landfill:** Burying waste in large pits.
- **Incineration:** Burning solid waste at very high temperatures (around 1000°C).
- **3R's:** The best approach: **Reduce, Reuse, and Recycle**.
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## 📋 8. COMPLETE EXERCISE SOLUTIONS
### **1. Differentiate Between:**
**a. Soft Glass and Hard Glass**
| Soft Glass (Soda-lime) | Hard Glass (Potash-lime) |
|---|---|
| Made using sodium carbonate ($Na_2CO_3$). | Made using potassium carbonate ($K_2CO_3$). |
| Has a lower melting point. | Has a higher melting point and is more durable. |
| Used for bottles, window panes. | Used for heat-resistant lab apparatus. |

**b. Organic and Chemical Fertilizers**
| Organic Fertilizers | Chemical Fertilizers |
|---|---|
| Made from decaying plants and animals. | Made from synthetic chemicals. |
| Improves soil health and texture. | Provides specific nutrients but can degrade soil over time.|
| Eco-friendly; does not cause pollution. | Overuse leads to water and soil pollution. |

### **2. Give Reasons:**
**a. Gypsum is added while manufacturing cement.**
**Answer:** Gypsum is added to cement to **slow down its initial setting time**. This provides sufficient time for mixing and application before it hardens.

**b. Bakelite is used for making handles of pressure cookers.**
**Answer:** Bakelite is a **thermosetting plastic** and a **poor conductor of heat**. It does not soften upon heating, making it a safe and ideal material for insulating handles on hot cookware.

**c. Lead crystal glass is used for expensive decorative items.**
**Answer:** Lead crystal glass contains lead oxide, which gives it a **high refractive index**. This makes the glass sparkle brilliantly when it catches the light, making it desirable for expensive glassware and decorative pieces.

**d. Detergent water is not useful for plants.**
**Answer:** Detergents contain synthetic chemicals (like phosphates) that can be harmful to plant life and can alter the pH of the soil, making it unsuitable for growth.

**e. Plastic is used for making surgical equipment.**
**Answer:** Medical-grade plastics are used because they are lightweight, can be easily sterilized, are shatter-proof, and are chemically inert, meaning they do not react with body tissues.

### **3. Answer the following questions:**
**a. What is glazing?**
**Answer:** Glazing is the process of applying a thin, glassy coating to ceramic objects and then firing them. This makes the ceramic shiny, smooth, waterproof, and more durable.

**b. How is compost manure prepared?**
**Answer:** Compost manure is prepared by collecting biodegradable wastes (like vegetable peels, leaves, animal dung) in a pit. The waste is layered with soil and left to decompose for 3-4 months. Microorganisms break down the organic matter into nutrient-rich humus, which is an excellent fertilizer.

**c. Why are plastics so widely used?**
**Answer:** Plastics are widely used because they are lightweight, strong, durable, cheap, waterproof, and can be easily molded into any shape. They are also poor conductors of heat and electricity and do not corrode.
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## ✅ 9. CHAPTER CHECKLIST & EXAM TIPS
**Exam Hotspots 🔥:**
-   **Give Reasons:** This section is the most important. Master the reasons for gypsum in cement, Bakelite in handles, Pyrex in labs, and why detergents are better.
-   **Differentiations:** Be perfect with the tables for Soap vs. Detergent, Thermoplastics vs. Thermosetting, and Soft vs. Hard Glass.
-   **Definitions:** Know the definitions of Saponification, Polymerization, Mortar, Concrete, RCC, and Glazing.
-   **Types of Glass:** Remember the special raw material and one key use for each type of glass.

**Your Pre-Exam Checklist:**
- [ ] I can name the raw materials for ordinary glass and cement.
- [ ] I can explain why gypsum is added to cement.
- [ ] I can differentiate between thermoplastics and thermosetting plastics with examples.
- [ ] I can explain why detergents work in hard water but soaps do not.
- [ ] I can list two benefits of organic fertilizers over chemical fertilizers.
- [ ] I can define solid waste management and name two methods of disposal.
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## 🎊 CONCLUSION
The materials we use every day are a product of brilliant chemistry. From the glass in our windows to the cement in our homes, understanding their properties helps us appreciate the world and make smarter choices. This chapter connects directly to our lives and highlights our responsibility to manage these materials sustainably to protect our environment.
**Key to Success:** Connect Concepts to Real-Life Objects + Master the 'Give Reasons' + Revise the Differences = Excellent Score!