I. Molar Conversions
What is a mole?
 A counting ___________________________
 ______________________________ number
 1 mole = ______________________________
Mole/Particle Conversions
(Particles/mol)
________________________
________________________
Particles =
_________________________________________________________________, etc
Example 1:
How many molecules are in 2.50 moles of C12H22O11?
Example 2:
If you have 2.23 x 1018 atoms of sodium, how many moles is that?
II. Molar Mass
 Avogadro discovered the relationship between _____________________________ and
____________________________
 This was used to find the relationship for particles in a __________
Representative Particles and moles
Substance
Chemical
Formula
Representative
Particle
Carbon
Nitrogen Gas
Calcium Ion
Magnesium Flouride
Mass of 1 mole of an element or compound
____________(on the PT) tells the...
 _______________________ (amu)

________________________ (g/mol)
Representative
particle in 1 mole
Molar Mass Examples:
Carbon
Water
Aluminum
Sodium Chloride
III. Molar Conversions
Mass in
Grams
Moles
Number of
Particles
Example 1: How many moles of carbon are in 26 g of carbon
Example 2: Find the mass of 2.1  1024 molecules of NaHCO3.
Example 3: How many moles are in 22.5 grams of potassium?
GASES & MOLES
•
•
•
•
•
•
Many of the chemicals we deal with are ____________
They are difficult to weigh.
Need to know how many __________ of ______ we have.
Two things effect the volume of a gas
______________ and ______________
Compare at the same temp. and pressure.
STANDARD TEMPERATURE AND PRESSURE




___ºC and ____ atm pressure abbreviated _______
At STP ___ mole of gas occupies ___________ Liters
Called the _________ volume
Avogadro’s Hypothesis - at the _______ temperature and pressure _________ volumes of gas
have the __________ number of particles.
Molar Volume
 Avogadro's Theory: _______ _________ containing equal numbers of molecules occupy
__________ volumes under similar conditions.
 Standard Temperature and Pressure: 0OC and 1 atm.
 *Molar Volume at STP = ________________ L

Example 1: What is the mass of 3.36 L of ozone gas, O3, at STP?

Example 2: How many molecules of hydrogen gas, H2, occupy 0.500 L at STP?
Mole Bridge
(for ONE Substance)
To convert from one box to another, multiply by the conversion next to the arrow going in the direction you want.
___________ of
________ or molecules of
6.02 x10 23 atoms / molecules
x

1 mole
x
(Use the Molar Mass from the PT)
6.02 x 10
23
1 mole

atoms / molecules
x
1 mole

grams
moles of
x
1 mole

22.4 L
x
22.4 L

1 mole
liters of gas at STP
x
grams

1 mole
Formula Calculations
Percent Composition

_______________________________________________________________________________
_______________________________________________________________________
% mass of element =
Ex 1 : Find the % composition of Sulfur and copper in the compound Cu2S.
Gas Properties
Kinetic Molecular Theory.
Particles in an ideal gas…
 have no _________________
 have elastic collisions
 are in constant, random, straight-line ________________

don’t ______________ or ______________ each other

average kinetic energy is _____________ proportional to the absolute __________________
To change pressure you can:
The gas laws focus on these relationships.
Characteristics of Gases
 Gases _______________ to fill any container

o random motion, no attraction

Gases are ___________ (like liquids)
o no attraction

Gases have very low _________________
Gases can be ____________________
o

Gases undergo ______________ &
__________________
o
o _____ ____________= lots of empty space
Describing Gases
Gases can be described by their:


no volume = lots of empty space


random motion
Temperature
- Temperature: Every time temperature is used in a gas law equation it must be stated in
.
The conversion:
Pressure:

K=
Pressure of a gas is the _______________ of its particles exerted over a unit ___________
(number of ________________ against a container’s walls)
Pressure =
Pressure may have different units: torr, millimeters of mercury (mm Hg), atmospheres (atm), Pascals (Pa),
or kilopascals (kPa).
torr =
mm Hg =
atm =
Pa =
kPa = ________ psi
Standard Temperature and Pressure (STP)
STP is defined as
°C (
K) and
**The volume of 1 mole of gas at STP is
atm. (_________kPa)
L
Practice: Convert the following pressures:
A) .830 atm =
kPa
B) 1.75 atm=
psi
The Gas Laws
Boyle’s Law:
Robert Boyle investigated the relationship between the ______________ and ____________ on a gas,
holding the temperature constant. He found that pressure and volume are
related.
 This is done while having a constant ________________ and ________________.
As pressure
volume
Boyle’s Law:
Ex: A gas occupies 100. mL at 150. kPa. Find its volume at 200. kPa.
Charles’s Law:
Jacques Charles investigated the relationship of __________________ & ____________ in a gas. He
found that the volume of a gas and the Kelvin temperature of a gas are
related.

As __________________ increases, Temperature _________________
Charles’s Law:
Remember: Temperature MUST be stated in KELVIN.
Ex 2: A gas occupies 473 cm3 at 36°C. Find its volume at 94°C.
Ex 3: The volume of a sample of gas is 43.5 L at STP. What will the volume of the gas be if the
temperature is increased to 35.4°C?
Gay-Lussac’s Law
Since temperature and volume are related, it would make sense that temperature and pressure are related.
The equation for this will resemble Charle’s law.
Equation:

The pressure and absolute temperature (K) of a gas are ___________________ related
• at constant mass & volume
Ex: A gas’ pressure is 765 torr at 23°C. At what temperature will the pressure be 560. torr?
Combined Gas Law
And in case that wasn’t enough, there is also the combined gas law which takes the ideas of the scientists
and melds them into one law which states:
Example : A gas occupies 7.84 cm3 at 71.8 kPa & 25°C. Find its volume at STP.
Ideal Gas Law & Gas Stoichiometry
Avagadro’s Law:



o
o
o
The volume of a gas ____________ or _____________, as its number of ___________ is being
increased or decreased.
The volume of an enclosed gas is ________________ proportional to its number of ___________.
Equal volumes of gases contain equal numbers of _____________.
at constant ________________ & _________________
true for __________ gas
_______ = number of moles
Avagadro’s Principle:
Merge the Combined Gas Law with Avogadro’s Principle:
Universal Gas Constant: R = _______________________________
R = _______________________________
Example 1: Calculate the pressure in atmospheres of 0.412 mol of Heat 16°C & occupying 3.25 L.
Example 2: Find the volume of 85 g of O2 at 25°C and 104.5 kPa.