Download Ch. 15 - Liberty Union High School District

Ch. 15
WATER
And
Solution Formation
Water is unique (video)
• Polar Molecular Compound (shape=bent)
• IMF = Hydrogen “bonds” = VERY STRONG
– Causes :
• High boiling point
• Low vapor pressure
• High surface tension
– Surfactant: disrupts H-bond
2
Solid Water (ICE)
• Unique structure due to H-bond
• Ice floats bc of structure (video)
– Less dense than liquid
• Open hexagon structure
or honeycombed shape
3
Solutions
• Solvent: Dissolving medium (does the dissolving)
•
•
•
•
Solute: the dissolved particles (gets dissolved)
Solvation: the dissolving process
“like dissolves like”
Water is called the UNIVERSAL SOLVENT
4
Solubility “Rules”
IONIC
Metal/nonmetal
Polyatomic ions
Roman numerals
Electrolytes
KCl, FePO3
POLAR
COVALENT
NM/NM eneg diff
>.5
COH, alcohol
(methanol, ethanol)
Sugars -ose
C2H5OH (ethanol)
C6H12O6 (sugar)
NONPOLAR
COVALENT
NM/NM eneg diff
<.4
-ene, ane, yne
endings - CH
Diatomic molecules
Br2
Toluene, benzene
C6H6
Oil, gasoline
5
Electrolytes
• Electrolyte: conducts electricity when
dissolved in water
– All ionic compounds are electrolytes
• Dissociate into ions.
6
Nonelectrolytes
• Nonelectrolyte: doesn’t conduct electricity
– Most molecular compounds
• Especially carbon based (organic) compounds
7
Hydrates
• Hydrate: water containing compound.
– Example: copper II sulfate pentahydrate
8
Deliquescent Compounds
• Deliquescent Compound: absorb water from
the air.
– Silica packets
– NaOH
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