Question

Write a short note on the following:
(i) Importance of pH in daily life
(ii) Micelle
(iii) Metals and Non-metals

Hint:

pH plays a crucial role in various natural and human processes, from digestion to agriculture. Micelles are useful for cleaning and digestion, while understanding the properties of metals and non-metals helps in material selection.

Answer 1

(i) Importance of pH in Daily Life:
pH is a measure of how acidic or basic a substance is, ranging from 0 to 14. It plays a vital role in various processes in daily life, including: 1. In the Human Body: - The pH of human blood is slightly alkaline (around 7.4), and any deviation from this range can affect bodily functions. The body's ability to regulate pH is crucial for maintaining health.
- The stomach uses hydrochloric acid (pH 1.5–3.5) to aid in digestion, and any imbalance in pH can lead to digestive issues like acidity or ulcers.
2. In Agriculture: - The pH of soil affects the availability of nutrients to plants. Most plants thrive in slightly acidic to neutral soil (pH 6–7). Extreme pH levels can lead to nutrient deficiencies and poor plant growth.
3. In Household Products: - Many cleaning products are formulated with an optimal pH level to effectively remove stains, grease, and dirt. For example, detergents, soaps, and shampoos are usually mildly acidic or neutral to be effective but safe.
4. In Swimming Pools: - The pH of swimming pool water must be maintained within a specific range (around 7.2 to 7.8) to ensure comfort and safety for swimmers. Proper pH balance helps to prevent eye irritation and promotes the effectiveness of chlorine.
(ii) Micelle:
A micelle is a structure formed when amphiphilic molecules, such as surfactants (detergents), are dissolved in water. These molecules have both hydrophilic (water-loving) and hydrophobic (water-repelling) parts. In a micelle:
- The hydrophobic tails of the surfactant molecules face inward, away from water, forming the core of the micelle.
- The hydrophilic heads face outward, interacting with the surrounding water. Micelles are essential in processes like cleaning, as they encapsulate oily substances in their hydrophobic core, allowing them to be washed away with water. Micelles are also critical in digestion, where bile salts form micelles that aid in the absorption of fats in the intestines.
(iii) Metals and Non-metals:
Metals and non-metals are two broad categories of elements, distinguished by their physical and chemical properties. 1. Metals: - Metals are typically solid (except mercury) and are good conductors of heat and electricity.
- They have high melting and boiling points, are malleable (can be hammered into thin sheets), and ductile (can be drawn into wires).
- Metals tend to lose electrons in chemical reactions, forming positively charged ions.
- Examples: Iron, copper, aluminum, and gold.
2. Non-metals: - Non-metals can be solid, liquid, or gas and are poor conductors of heat and electricity.
- They have low melting and boiling points and are brittle in the solid state.
- Non-metals tend to gain or share electrons in chemical reactions, forming negatively charged ions or covalent bonds.
- Examples: Oxygen, nitrogen, sulfur, and carbon.
Conclusion:
- Metals are essential for construction, electronics, and industrial uses, while non-metals are vital for life processes and are often used in medicines, agriculture, and energy production.
- Understanding the properties of metals and non-metals helps in selecting materials for different applications.