4.1 Environment - Water Chemistry.pdf

Water Essential substance with unique dissolving properties. Polar Molecule Unequal charge distribution within the water molecule. Hydrogen Bonds Strong dipole forces between H and electronegative atoms. Intermolecular Forces Attractions between molecules affecting physical properties. Boiling Point Water's boiling point elevated by hydrogen bonding. Permanent Dipole-Dipole Interactions Attraction between polar covalent molecules' charged regions. Specific Heat Water's high capacity to absorb heat energy. Water Hardness Concentration of dissolved calcium and magnesium ions. Water Hardness Rating Classification based on mg/L of CaCO3. Soft Water Water with hardness rating 0-60 mg/L. Moderately Hard Water Water with hardness rating 61-120 mg/L. Hard Water Water with hardness rating 121-180 mg/L. Very Hard Water Water with hardness rating over 180 mg/L. pH Measure of acidity or basicity in water. pH Formula pH = -log [H3O+] defines acidity. Acidic Water pH < 7 indicates excess H3O+ ions. Neutral Water pH = 7 indicates balanced H3O+ concentration. Basic Water pH > 7 indicates lower H3O+ concentration. Water Quality Parameters Key indicators of water's physical and chemical properties. Turbidity Cloudiness of water caused by suspended particles. Dissolved Oxygen Amount of oxygen available in water for organisms. Nutrients Phosphates and nitrates affecting water quality. Algal Bloom Rapid increase of algae in water bodies. Sewage Overflow Discharge of untreated sewage into water. pH of Natural Waters Measure of acidity or alkalinity in water. Estuary Where freshwater meets saltwater. Phosphates (PO4 3-) Nutrient causing pollution, less than 0.1 mg/L natural. Sources of Phosphate Pollution Includes manures, detergents, sewage, fertilizers. Nitrites and Nitrates (NO2-, NO3-) Major pollutants from fertilizers and livestock. Eutrophication Overproduction of vegetation due to nutrient loading. Ammonium (NH4+) Indicates organic contamination from waste materials. Dissolved Oxygen (DO) Oxygen available in water for aquatic life. DO Measurement Range Typically 0-18 ppm; 5-6 ppm needed for diversity. Impact of Organic Waste on DO Increases algae, decreases DO for aquatic organisms. Natural Causes of Low DO Includes sunlight, nutrient availability, weather changes. Artificial Causes of Low DO Human nutrient loading and river input changes. Turbidity Measure of water clarity or murkiness. Measuring Turbidity Using Nephelometric Turbidity Unit (NTU). WHO Turbidity Standards Drinking water should not exceed 5 NTU. Ideal Turbidity Level Should ideally be below 1 NTU. Sources of Nitrite Pollution Includes fertilizers, manures, and poor infrastructure. Effects of High Ammonium Indicates pollution from sewage or agricultural runoff. Natural Water Systems Require balanced nutrients for ecosystem health. Anthropogenic Sources Human activities contributing to water pollution. High Turbidity Cloudiness in water caused by suspended particles. Phytoplankton Microscopic plants that contribute to water turbidity. Sedimentation Rate Speed at which particles settle in water. Organic Detritus Decomposed organic matter affecting water quality. Gill Damage Harm to fish respiratory structures from pollutants. Eutrophication Excessive nutrient growth causing algal blooms. Anoxic Water Water depleted of oxygen, harming aquatic life. Bioaccumulation Chemical concentration in organisms over time. Biomagnification Increasing chemical concentration up the food chain. Mercury Poisoning Toxic effects from mercury exposure in water. Contaminants Harmful substances in water affecting health. Inorganic Pollutants Non-carbon-based harmful substances in water. Acidity Increased hydrogen ion concentration from pollution. Ammonia Pollution Toxic nitrogen compound from food processing. Heavy Metals Toxic elements like lead and mercury in water. Silt Runoff Sediment washed into water from land disturbances. Light Penetration Depth to which light can reach underwater. Sediment Suffocation Burial of larvae by settling particles. Nutrient Fertilizers Chemical compounds promoting plant growth in water. Storm Water Runoff Rainwater carrying pollutants into water bodies. Dredging Operations Removal of sediment affecting water quality. Bottom-Feeding Fish Fish species that disturb sediments, increasing turbidity. Water Quality Monitoring Systematic assessment of water pollution levels.