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Municipal water treatment ensures safe and clean drinking water. The process involves the following steps: 1. Coagulation and Flocculation Chemicals like alum (Al₂(SO₄)₃) are added to water to form flocs, which trap dirt and impurities. Equation: Al₂(SO₄)₃ + 3Ca(OH)₂ → 2Al(OH)₃ + 3CaSO₄ 2. Sedimentation The heavy flocs settle at the bottom of the tank, … Read more
Water pollution occurs when harmful substances contaminate water bodies, making them unsafe for humans and aquatic life. The major sources of water pollution include: Industrial Waste: Factories discharge toxic chemicals, heavy metals, and dyes into rivers and lakes. These pollutants reduce oxygen levels in water, harming aquatic organisms. Agricultural Runoff: Fertilizers and pesticides used in … Read more
Magnesium hydrogen carbonate decomposes upon heating, forming magnesium carbonate, carbon dioxide, and water: Mg(HCO₃)₂ → MgCO₃ + CO₂ + H₂O Related Questions: List the impurities present in rainwater. List toxic substances present in household wastes. In what ways do industrial wastes pollute water? What is water pollution? List some waterborne diseases. What are pathogenic microorganisms? What is hard water? … Read more
Hard water contains dissolved calcium and magnesium salts, making it difficult to form lather with soap. Soft water lacks these salts and lathers easily with soap. Related Questions: List the impurities present in rainwater. List toxic substances present in household wastes. In what ways do industrial wastes pollute water? What is water pollution? List … Read more
The four main water sources are oceans, glaciers and ice caps, groundwater, and surface water (rivers and lakes). Related Questions: List the impurities present in rainwater. List toxic substances present in household wastes. In what ways do industrial wastes pollute water? What is water pollution? List some waterborne diseases. What are pathogenic microorganisms? What … Read more
Disadvantages of water hardness Hard water forms scale in pipes and boilers, reducing efficiency. It requires more soap for washing, causes skin irritation, and leaves spots on dishes and laundry. Related Questions: List the impurities present in rainwater. List toxic substances present in household wastes. In what ways do industrial wastes pollute water? What … Read more
1. Boiling (for temporary hardness) Ca(HCO₃)₂ → CaCO₃ + CO₂ + H₂O 2. Using washing soda (for permanent hardness) CaSO₄ + Na₂CO₃ → CaCO₃ + Na₂SO₄ 3. Ion-exchange method Ca²⁺ + Na₂Z → CaZ + 2Na⁺ Related Questions: List the impurities present in rainwater. List toxic substances present in household wastes. In what ways … Read more
Acid rain contains sulfuric acid and nitric acid, which react with limestone (CaCO₃) in buildings, causing damage. The reaction is: CaCO₃ + H₂SO₄ → CaSO₄ + CO₂ + H₂O Related Questions: List the impurities present in rainwater. List toxic substances present in household wastes. In what ways do industrial wastes pollute water? What is … Read more
Ca²⁺ ions in hard water react with sodium zeolite (Na₂Z) to remove hardness: Ca²⁺ + Na₂Z → CaZ + 2Na⁺ Related Questions: List the impurities present in rainwater. List toxic substances present in household wastes. In what ways do industrial wastes pollute water? What is water pollution? List some waterborne diseases. What are pathogenic microorganisms? … Read more
When temporary hard water containing calcium hydrogen carbonate is boiled, it decomposes into calcium carbonate, carbon dioxide, and water: Ca(HCO₃)₂ → CaCO₃ + CO₂ + H₂O Related Questions: List the impurities present in rainwater. List toxic substances present in household wastes. In what ways do industrial wastes pollute water? What is water pollution? List some … Read more