50 terms

Adv. Chem. - Chapter #15 - Water & Aqueous Systems

Chapter #15 review for advanced chemistry

Terms in this set (...)

Many unique and important properties of water including its high surface tension and low vapor pressure is due to _________________.
hydrogen bonding
The bond angle in a water molecule.
105 degrees
Water molecules on the surface that pull inward because water is attracted more to other water molecules than to the air and minimizes the surface area of liquids.
surface tension
A substance that interferes with the hydrogen bonding between water molecules and thereby reduces surface tension.
Hydrogen bonding tends to hold onto nearby water molecules and prevents them from easily escaping the liquid form and evaporating. This results in water having a _________ vapor pressure.
The structure formed by water as it freezes into a solid due to its polarity and the attraction of it's hydrogen atoms for the nearby water molecule's oxygen atom.
crystal lattice
The temperature in Celsius in which water is the densest.
4 degrees
Water forms a crystal lattice as it freezes. This makes the ______ get larger and the density become less. This causes ice to float on liquid water.
If ice didn't float on water, no _______ would exist on Earth.
As water gets warmer than 4 degrees Celsius, it begins to __________ and its density becomes ________.
expand, less.
Water that contains dissolved substances.
aqueous solutions
The dissolving medium in the solution is called this.
Dissolved particles in the solution are called this.
As a solute dissolved water molecules surround the ionic compound due to it's polar nature, and the solute disassociates. This process is called ________.
Like dissolves _______.
A compounds that conducts an electric current when it is in an aqueous solution or in the molten state.
All ionic compounds are electrolytes because they __________ into ions in solution.
A compound that does not conduct an electric current when dissolved in water or in the molten state.
When nearly all the the particles dissociate and conduct an electric current such as soluble salts, inorganic acids, and inorganic bases it is called a(n) _____________.
strong electrolyte
Conducts an electric current poorly because only a fraction of the solute in a solution exists as ions such as ammonia, organic acids and organic bases.
weak electrolytes
A compound that contains water of hydration.
Name this hydrate CaCl2 dot 2H2O
calcium chloride dihydrate
Name this hydrate - FeSO4 dot 7H20
iron (II) sulfate heptahydrate
Write the formula for barium hydroxide octahydrate.
Ba(OH)2 dot 8H2O
Write the formula for magnesium sulfate heptahydrate.
MgSO4 dot 7H2O
As crystals lose water of hydration, they ___________ and become coated with white powder of the anhydrous compound.
Hydrated salts that have low vapor pressure remove water from moist air to form higher hydrates. These compounds are called ____________.
A substance used to remove moisture from the air and create a dry atmosphere are called this.
What is the % by mass of water in Na2SO4 dot 10H2O?
55.9% water
What is the % by mass of the anhydrous portion of the hydrate CuSO4 dot 5H2O?
63.9% CuSO4
What is the % by mass of water in the hydrate CaCl2 dot 6H2O?
49.3% water
These compounds can remove water from the air and are so hygroscopic that they become wet in the air such as sodium hydroxide and are called __________________.
A mixture from which particles settle out upon standing are called _____________.
Size of a suspension particle.
> 1000 nm
A heterogeneous solution containing particles that range in size from 1 nm to 1000 nm and spread throughout the dispersion medium.
Gelatin, glue, paint, aerosol sprays, and smoke are _______________.
colloid examples
Muddy water, gravy, sauces are ________________.
suspension examples
A homogeneous solution of particles less than 1-nm, that exhibit no Tyndall effect.
Saltwater, tap-water, sugar water are _______________.
solution examples
The scattering of light by colloidal particles is called the __________.
Tyndall effect
The chaotic movement of colloidal particles caused by the collisions of molecules in the dispersal medium are called______________, which prevent colloidal particles from settling out of solution.
Brownian motion
Colloidal particles that remain suspended because they become charged by absorbing ions from the dispersing medium onto their surface and the repulsion of the like-charged particles prevents the aggregates that would have an tendency to settle out are called this.
A colloidal dispersion of a liquid in a liquid.
A substance such as egg yolk that can cause a heterogeneous mixture such as vinegar and vegetable oil to mix and not separate are called _______________.
emulsifying agent
True or false? Colloids cannot be filtered to separate the contents.
True or false? Suspensions cannot be filtered to separate the contents.
True or false? Solutions cannot be filtered to separate the contents.
True or False? Colloids and suspensions both exhibit the Tyndall Effect.
Would NaOH dissolve in water?
If you add ions with a charge opposite that of the colloidal particles, what happens?
The colloid becomes destroyed.