unit 11 chem

i hate chemistry i hate 7th period thank you

miscible

liquids that dissolve freely in one another (polar solvents) - when 2 liquids can mix and form a homogeneous mixture (solution)

immiscible

liquids that do not dissolve in each other (polar and nonpolar solvents)

Example: oil in water, lava lamp - when 2 liquids DON’T mix and form a heterogeneous mixture (suspension)

Solubility

a measure of how much solute can dissolve in a certain solvent.  

Solute

the “stuff” you dissolve (usually a powder)

Solvent

the “stuff” that does the dissolving (usually water)

Solution

end product of dissolving solute in solvent

Molarity

A unit of concetration - the number of moles of solute dissolved per liter of solution, Anything you can dissolve in water has a molarity.

molarity formula

M =  moles of solute  (mol)/

        liters of solution  (L)

Dilutions

  When you do a dilution, you add water to a solution.  The resulting solution gets LESS CONCENTRATED or MORE DILUTE!

dilutions formula

 M₁V₁ = M₂V₂

M is molarity of the solution

M₁ is initial molarity

M₂ is final molarity

V is volume of the solution

V₁ is initial volume

V₂ is final volume (total volume) 

Spectator Ions

Ions that do not participate in the chemical reaction.  (They “watch”!)  They must be in EXACTLY the same form on both sides of the chemical reaction. 

Dissolving a solute

heat, crush solute, stir (collisions between water and solute)

unsaturated solution

More solute can still dissolve in the solution 

saturated solution

The limit of solubility.  The place where not one more grain of solute can dissolve in the solution

supersaturated

Unstable solution.  Extra steps had to be taken to “force” more solute to dissolve.  This is the solution where crystals can form. 

dilute solution

A dilute solution

A concentrated solution

has large amounts of solute dissolved in it.  There is a point where so much solute is added that it can no longer dissolve (supersaturated).

like dissolves like

polar and polar solvents, non polar and non polar solvents

electrolyte

solution that conducts electricity.  Ionic bonds break apart (dissociate) when dissolved in water and usually form electrolytes.

non-electrolyte

solution that does not conduct electricity.  Covalent bonds usually do not break apart (dissociate) when dissolved in water and do not form electrolytes.   

Colligative properties

a property of a solution that doesn’t depend on the identity of the solute, but on HOW MUCH STUFF is dissolved in the solution

• boling point elevation

• freezing point depression

boiling point elevation

The “extra particles” in 

the solution block the 

solvent from being able 

to evaporate (escape).  It 

takes more energy for 

the solvent to evaporate.  

Freezing Point Depression

The “extra particles” in 

the solution block the 

solvent from being able 

to form a lattice (and

freeze)  A lower 

temperature is needed

to freeze.  

Example:  Adding salt to icy 

streets

It works down to -9°C!

water is polar

Water is the universal solvent.

Water has incredible dissolving power!!!! (This is why we use water to clean things)

The hydrogen bonds in water rip solutes apart! 

cohesion

water molecules stick to other water molecules

surface tension

Ability of water to "pile up" on itself

adhesion

Water molecules stick to other materials

capillary action

Water can easily flow up a narrow tube

universal solvent

water (can dissolve many things)

water is good

hydrogen bonding