60 likes | 204 Views
Chapter 17 Section 1. Liquid Water and Its Properties: -it is foundation of all life -makes up 70% of body of humans -can exist in all three phases -Water is a triatomic molecule made up of three atoms -Water is polar -bonding e- shared unequally
E N D
Chapter 17 Section 1 Liquid Water and Its Properties: -it is foundation of all life -makes up 70% of body of humans -can exist in all three phases -Water is a triatomic molecule made up of three atoms -Water is polar -bonding e- shared unequally *caused by electronegativity diff.
-Many properties of water are due to hydrogen bonding -water has strong intermolecular bonds between the hydrogen atoms and it is very difficult to break these bonds
Properties Resulting From H-Bonding • high surface tension • low vapor pressure • high specific heat capacity • high heat of vaporization • high boiling point
Surface Properties -surface of water acts as a skin -page 476, fig. 17.4 -can overfill a glass -both are explained by surface tension: -inward force or pull that tends to minimize the surface area of a liquid -holds water in shape of sphere -can be reduced by adding a surfactant: interferes with hydrogen bonding ex- soap
Low Vapor Pressure vapor pressure- pressure right above the surface of a liquid, caused by molecules escaping to gas phase -b/c of H-bonding the molecules cannot escape as easily so vapor pressure is low -if not lakes, ponds, oceans would easily evaporate
High Specific Heat Capacity specific heat- amount of heat needed to raise temp. of 1g of a substance 1°C *due to H-bonding -pool vs. car surface -this property helps regulate temps