WATER

• High specific heat capacity


  • Water can absorb and retain heat without significant temperature changes
  • Crucial for regulating Earth's climate and maintaining stable temperatures in aquatic environments
• High heat of vaporization


  • Water requires substantial energy to transition from liquid to vapor
  • Cools surfaces (e.g., sweating) and helps moderate temperatures
• Density anomaly


  • Unlike most substances, water is denser in its liquid state than in its solid state
• Universal solvent


  • Water's polarity allows it to dissolve many substances
  • Essential for biological processes and the transport of nutrients
• Cohesion


  • Water molecules stick together due to hydrogen bonding

  
• Adhesion


  • Water adheres to other surfaces (e.g., plant capillary action)
• Surface tension


  • Water's cohesive forces create a "skin" on its surface
  • Insects can "walk" on water due to surface tension
• Capillary action


  • Water can climb up narrow tubes (e.g., plant roots, paper towels) against gravity
• pH neutrality


  • Pure water has a pH of 7 (neutral)
  • It can act as both an acid (donating H⁺ ions) and a base (accepting H⁺ ions)
• Transparency


  • Water is transparent to visible light
  • Allows sunlight to penetrate aquatic ecosystems
• pH of water from common sources

  • Rainwater (acidic)
  • Groundwater (alkaline)
  • Treated water (alkaline)
• Material that contributes to turbidity

  • Clay and silt particles
  • Algae and plankton
  • Dissolved colored organic compounds
  • Very tiny inorganic and organic matter
• Effects and importance of turbidity

  • Reduced light availability impacts aquatic ecosystems
  • Altered conditions for aquatic plants and animals
  • Cloudy water affects swimming and aesthetics
  • Sedimentation harms fish habitats
  • Turbidity provides attachment sites for pollutants like metals and bacteria
• Hard water


  • Water that forms when it percolates through deposits of limestone, chalk, or gypsum—minerals rich in calcium and magnesium compounds
  • These minerals dissolve in the water, leading to its hardness