Gases can only form true solutions with compounds/elements in this other phase of matter.
Other gases - liquids or solids in a gas can only form colloids or suspensions, not solutions
100
What are the 4 ways to measure concentration?
Percent by Mass
Molarity
Normality
Molality
100
The amount of change from a solvent's normal properties to the new properties depends only on what factor?
The number of solute particles present
100
What is the biggest difference in how colloids differ from solutions?
Solutions mix extremely well, all particles are dispersed in each other
Colloids have clusters/pockets of compounds that stick together, still mixed just not as well
100
In dissociation the attractive forces between molecules must be overcome before a substance can be dissolved. What is used to break these bonds?
Heat energy
200
Name two factors which affect solubility.
Temperature - generally more heat = more soluble
Pressure - more pressure = more solubility for gases only
200
Find the molarity of sugar in the solution:
A solution contains 0.22 mole of salt, 1.45 moles of sugar, 0.75 mole of artificial flavors, and 1.3 moles of carbon dioxide in 3 liters of solution.
1.45 / 3 = 0.48 M
200
Why does the vapor pressure of a solvent decrease as solute molecules are added?
Solute particles compete for spots on the surface, limiting how many solvent molecules have the opportunity to evaporate.
200
What is the Tyndall effect?
Particles of a colloid are large enough to deflect and scatter light passing through
200
When will a substance boil?
When the vapor pressure matches/exceeds atmospheric pressure.
300
When a solution is supersaturated how does the amount of solute compare to the carrying capacity of the solvent?
More solute than carrying capacity - only possible by heating a solvent to increase carrying capacity and then slowly cooling
300
Find the percent by mass of sugar in the solution:
1 can of A&W Root Beer (12 fl oz) weighs 370 g and has 152 calories, 39 g of sugar, & 0.048 g sodium.
( 39 / 370 ) x 100% = 10.54%
300
Adding 1 mole of a mystery solute to a solvent raises it's boiling point from 132 degrees C to 134.2 degrees C. What is the change in boiling point (delta T bp) per 1 mole?
134.2 - 132 = 2.2 degrees C / mole
300
These can block intermolecular forces and cause a particle to fall out of a colloid, in a process called coagulation.
Flocculating agents
300
Eggs naturally contain _________ _______ and so they are used in many foods to keep oils and water from separating.
Emulsifying agents
400
Polar substances will tend to dissolve _______ _______, while non-polar substances will tend to dissolve ______ ______.
Find the molality of sodium in the solution:
1 can of A&W Root Beer (12 fl oz) weighs 370 g and has 152 calories, 0.22 mole of sugar, 0.00082 mole of sodium, & 0.0001 mole of potassium.
0.00082 / (370 / 1000) = 0.0022 m
400
Adding 3 moles of a mystery solute to a solvent lowers it's freezing point from 45.6 degrees C to 36.3 degrees C. What is the change in freezing point (delta T fp) per 1 mole?
( 36.3 - 45.6 ) /3 = -3.1 degrees C / mole
400
If the flocculating agents are removed from a particle that has fallen out of a colloid, the particle may rejoin the colloid in a process called ________.
Peptization
400
Why does the freezing point of a solvent decrease when solute is added?
Any added solute increases the randomness of the system (increased entropy) and makes it harder to form nice orderly solid forms.
500
State the 3 dissolving mechanisms and place them in the order which they happen.
Dissociation, Solvation, Diffusion
500
Find the normality of a 1.6 M solution of AlBr3:
1.6 x 3 / 1 = 4.8 N
3 comes from the number of electrons given by aluminum in the AlBr3 compound.
500
The Kfp (molal freezing point depression constant) for a solvent is 12.7 degrees C / mole. The normal freezing point of the solvent is 147.5 degrees C. What would the new freezing point be if 3.74 moles of any solute were added?
147.5 - (12.7 x 3.74) = 100 degrees C
500
The only phase combination that cannot make a colloid is a _______ - ________ combination. (i.e. solid-liquid)
Gas - gas
The particles are too small and too energetic. They mix extremely well together and do not have pockets/clusters of particles.
500
What is an azeotrope? Is it a miscible or immiscible solution?
Mixture of liquids that has a constant boiling point and can't be separated by normal distillation. It is a type of miscible solution.