Chapters 7 and 9

a homogenous mixture of two of more compounds

ex. sugar in water, oxygen in watere, air, dental fillings, saline

• the solute can't be filtered out
• always stays mixed
• particles are always in motion
• volumes are not additive
• may have different properties

component in the greater extent

component in the lesser extent ( you may have more than one)

• exist in any of the three states
• solids:dental fillings 14K gold, sterling silver
• liquid:saline, vodka, vinegar, sugar water
• gas:the atomsphere, anesthesia gases

a measure of how much a solute can be dissolved in a solvent

grams/mL

• temperature
• pressure
• polarity

when a solution contains as much solute as it can at a given temperature

can still dissolve more

have dissolved all you can (max. amount)

temporarily has dissolved more than normally would be dissolved at the certain temp.

solubility decreases when solution temp. increases

solubility increases when solution temp. increases

• little effect of solid and liquids
• will greatly increase solubility of gases

mass solution(g)/ total volume(mL) X 100

volume solute (mL)/ total volume (mL) X 100

the solution consists of 2 parts, the solute + the solvent. watch how the problem is worded

mass solute (g)/ total mass (g) X 100

moles solute/ liters of solution (1)

• recognizes that compounds have different formula weights
• A 1 M solution contains the same number of molecules as 1 M of ethanol
• []- special symbol which means molar (mol/l)

• moles/ liters
• allows 1 liter unless told otherwise

grams/liters

liter/ moles

once you have a solution; it canbe diluted by adding more solvent. this is also important for materials only available as solutions

• M₁V₁=M₂V₂
• C₁V₁=C₂V₂
• Any volume or concentration unit can be used as long as you use the same units on both sides of the equation

• extension of earlier stoichiometry problems
• first step is to determine the number of moles bases on solution concentration and volume
• final step is to convert back to volume or concentration as required by the problem
• you still need a balanced equation and must use the coefficiant for working the problem

• ionic compounds in polar solutions
• dissociate in solution to make ions
• conduct electricity
• may be strong (100% dissociation) or weak (less than 100%)

• do not conduct electricity
• solute is dispersed but does not dissolve

when an ionic solid dissolves in water the polar solvent removes ions from the crystal lattic

covalent compounds do not dissociate

• when ionic materials dissolve in water
• they dissociate: we show them as ions

the pressure required to stop osmosis. the amount of external pressure applied to the more concentrated solution to stop the passage of solvent molecules across a semipermeable membrane

osmotic pressre=nMRT

• "bulk" properties that change when you add a solute to make a solution
• based on how much you add
• effect of ionic materials is based on number of ions produced
• vapor pressure lowering
• freezing point depression
• boiling point elevation
• osmotic pressure

all colligative properties are based on Raoult's Law

when a solute is added to a solvent, the presssure of the solution is due to the parital pressure of the solvent

• when you add a solute to a solvent, the melting point goes down
• the more you add, the lower it gets
• this will only work until you reach saturation
• FP depression=(number of particles)(freezing point)(molerity)

• when you add a solution to a solvant, the boiling point will go up
• the more you add, the hight it goes
• it will only work until you resach saturation
• BP elevation= (number of particles)(freezing point)(molerity)