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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
Carbon dioxide dissolves in rainwater to form carbonic acid, which reacts with limestone (CaCO₃) as follows: H₂CO₃ + CaCO₃ → Ca(HCO₃)₂ 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 … Read more
When slaked lime (Ca(OH)₂) reacts with alum (Al₂(SO₄)₃), it forms aluminum hydroxide and calcium sulfate: Al₂(SO₄)₃ + 3Ca(OH)₂ → 2Al(OH)₃ + 3CaSO₄ 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 … Read more
Lakes and streams become polluted due to industrial waste discharge and agricultural runoff containing fertilizers and pesticides. Household sewage and plastic waste also contribute to water pollution. 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? … Read more
Hard water contains high concentrations of dissolved calcium and magnesium salts. It is undesirable because it forms scale in pipes and boilers, reduces soap lather, and causes skin dryness. It also leads to inefficient washing and increased detergent usage Related Questions: List the impurities present in rainwater. List toxic substances present in household wastes. In … Read more
Pathogenic microorganisms are harmful bacteria, viruses, fungi, or parasites that cause diseases in humans and animals. Examples include E. coli, Salmonella, Vibrio cholerae, and Giardia lamblia. 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
Common waterborne diseases include cholera, typhoid, dysentery, hepatitis A, and giardiasis. These diseases spread through contaminated drinking water and poor sanitation. 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? What are pathogenic microorganisms? What is hard … Read more