ch 15 Flashcards
the intermolecular attraction among water molecules results in
the formation of hydrogen bonds
surface tension
the inward force that tends to minimize the surface area of a liquid
water has a _____ surface tension
high
surfactant
any substanec that interferes with the hydrogen bonding between water molecules and therefore reduces surface tension
water has _____ vapor pressure
low because of hydrogen bonds
the structure of ice is
a regular open framework of water molecules arrnaged like a honeycomb
the molar heat of fusion
heat absorbed by one mole of a solid subtsance as it melts to a liquid at a constant temp
the molar heat of solidification
the heat lost when one mole of a liquid solidifies at a constant temp
the quantity of heat absorbed by a melting solid is
exactly the same as the quantity of heat released when the liquid solidifies
the molar heat of vaporization
the amount of heat necessary to vaporoize one mole of a given liquid
aqueous solution
water that contains dissolved substances
solvent
the dissolving agent
solute
the dissolved particles
a _____ dissolves the _____
solvent, solute
solvents and solutes may be
gases, liquids, or solids
solute particles can be
atoms, ions, molecules
solvation
the process by which the positive and negative ions of an ionic solid become surrounded by solvent molecules
polar solvents dissolve
ionic and polar compounds
nonpolar solvents dissolve
nonpolar compounds
electrolyte
a compound that conducts an electric current in an aqueous solution
all ionic compounds are
eloctrolytes because they dissociate into ions
weak electrolyte
conducts electricity only in a fraction of the solute
nonelectrolyte
a compound that does not donduct an electric current
hydrate
a compound that contains water of hydration
efflorescent hydrates
a hydrate that will give water to the air if the air is drier
hygroscopic hydrates
a hydrate that will remove h2o from the air
deliquescent
will remove h2o fro the air until it is a solution
suspension
a mixture from which particles settle out upon standing
the particles of a suspension are much _____
larger
suspensions are
heterogeneous
colloid
a heterogeneous mixture containing particles that range in size from 1nm to 1000 nm
the tyndall effect
the scattering of visible light by colloidal particles
solutions do not
scatter light
brownian motion
the chaoitc movement of colloidial particles
brownian motion is caused by
the collisions of the molecules of the dispersion medium with the small colloidal partciesl
a colloidal system can be destroyed by
the addition of ions that have a charge opposite to that of the colloidal particles
emulsions
a colloidal dispersion of a liquid in a liquid
an ______ is essential for the formation of an emulsion
emulsifying agent
cohesion
water molecules sticking t themselves
adhesion
water molcules sticking to other substances
capillary action
the adhesion to the walls of a substance is stronger than water’s cohesion to itselfl
how many hydrogen bonds can each water molecule form
4
specific heat
the heat reqired to raise the temp by 1 C
why does water have high specific heat
hydrogen bonds
hydrophobic
repels water
hydrophillic
can mix with water
miscibile
forming a homogeneous mixture when added together
