LP

Properties of Water

  • Cohesion: the tendency of molecules of the same kind to stick together

    The water molecules stays connected to the other water molecules

  • Adhesion: the tendency of two different kinds of molecules to stick together

    • Capillary action: the ability to move something up a surface
    • Ex: a straw in a glass of water has water slightly higher than the rest: the water rises using adhesion towards the straw, and the rest of the water rises using cohesion

  • Surface tension: a measure of how difficult it is to break the surface of a liquid

    • Hydrogen bonds cause water to stay together

    The water droplet will not break because the bonds of of the molecules will not break

    This type of bug can walk on water because it is light enough that it does not break the bonds of the molecules

  • Moderate temperature

    • Thermal energy: energy associated with the random movements of atoms and molecules
    • Heat: transfer of thermal energy from hot → cold
    • Temperature: measure of intensity of moving atoms
    • A lot of heat needed to be absorbed for water to change temperature
    • High heat capacity
    • Raising temperatures → bonds must break to vibrate faster, despite high surface tension
    • Lowering temperatures → bonds must break to evaporate, despite high surface tension

  • Major solvent

    • Solvent: dissolving agent
    • Solute: dissolved substance
    • Solution: solvent + solution
    • Aqueous solution: solution where the solvent is water
      • Charge of the water molecules breaks about other molecules, causing them to dissolve

    The charge of the water molecule breaks up the bonds of the solute