Class Blog 11-12-13

Class Blog 11-12-13

We started out by going over what will be on the test and what will not be on the test.  Next we went over colligative properties that we need to know.

Things not included in this unit:

-Molarity is not the only way to measure concentration!

-molality

-mass percent

-mole fraction

-volume percent

-parts per million (ppm)

-parts per billion (ppb)

-How to calculate the colligative effect of a solute in a solvent.

Colligative properties notes:

-Physical properties of solutions that depend on how many solute particles are present... not on what the solute is.

-Adding any kind of solute (mixing “pieces” in with a solvent) will change the way the solvent behaves.

Ones we need to know:

1. Boiling point goes up. (temp at which solvent boils).

2. Freezing point goes down. (temp at which solvent freezes).

3. Vapor pressure goes down.

4. Osmotic pressure goes up.

-The more pieces of solute in the solvent, the greater the effect on colligative properties.

  ex. C6H12O6 (s) ---> C6H12O6 (aq) 1 piece

NaCl (s) -------> Na+ (aq) + 2Cl- (aq) 2 pieces

CaCl2 (s) ------> Ca2+ (aq) + 2Cl- (aq) 3 pieces *Biggest Effect

CO2 (g) --------> CO2 (aq) 1 piece

Homework:

STUDY!!!

STUDY!!!

STUDY!!!

Reminders for Test:

-Study session for the test is at 7 am tomorrow (11-13-13)

-The video going over the study packet will be posted on moodle by 4 pm today.

-The stoichiometry precipitate worksheet is extra practice for the test (this was handed out last week)

Good Luck on the test everyone!!!

Next scribe is Dana S.