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PROPERTIES OF WATER. Structure of Water. Shape 105 o angle Polar molecule – negative and positive pole. Hydrogen Bonding. Hydrogen Bonds Occurs with polar molecules Between hydrogen and an electronegative atom in a nearby molecule (in this case: water). Surface Tension.
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Structure of Water • Shape 105o angle • Polar molecule – negative and positive pole
Hydrogen Bonding • Hydrogen Bonds • Occurs with polar molecules • Between hydrogen and an electronegative atom in a nearby molecule (in this case: water)
Surface Tension • Cohesion: another name for attractive forces of molecules to each other • each molecule of water is attracted in all directions (perhaps as many as four other water molecules) through hydrogen bonding • there is an inward force or pull which minimizes the surface area of any liquid. This causes surface tension
Surface Tension • Adhesion: ability of water molecules to be attracted to solid surfaces
Meniscus • is a curve in the surface of a liquid and is produced in response to the surface of the container or another object. • Surface Tension acts on concave menisci to pull the liquid up
Capillary Action • Adhesion of water molecules to the sides of a glass capillary tube pulls the water molecules up the sides of the tube. • The cohesion of the water molecules to each other, pulls the rest along
Hydrate • Compounds formed by the union of water with some other substance • Typically crystallized salts • Example: CuSO4 · 5H2O
Anhydrous • A substance that is not in contact with water • Water has been removed When the water from MgSO4·7H2O is driven off it becomes MgSO4, an anhydrous compound.
Viscosity • property of a fluid that offers resistance to flow • Something that is viscous has a cohesive (molecules attracted to each other) and sticky fluid consistency • Example: oil