Avogadros Principal & Molar Volume LG: I can use Avogadros
Principal to equate volume and number of entities in a gas.
Slide 2
Avogadro's Principal Avogadro determined that different gases
with equal volume, pressure, and temperature must contain the same
number of particles
Slide 3
Avogadro's Principal (cont.) We can explain this using
kinetic-molecular theory, but this concept was not understood in
Avogadros time
Slide 4
Sample Problem 1 A balloon with a volume of 34.5 L is filled
with 3.2 mol of helium gas. To what volume will the balloon expand
is another 8.0 g of helium is added? (assuming pressure and
temperature remain constant)
Slide 5
Molar Volume of a Gas Under standard conditions, 1 mole of a
gas (any gas) will occupy a constant volume STP (0C and 101.3 kPa)
= 22.4 L SATP (25C and 100 kPa = 24.8 L STP V = 22.4 L
Slide 6
Sample Problem 2 A sample of helium at SATP has a mass of 32.0
g. What volume does this mass of gas occupy?
Slide 7
Law of Combining Volumes Avogadros theory explained a previous
observation about combining gases Joseph Gay-Lussac had previously
observed that gases react in whole-number ratios (just like the
coefficients in a balanced equation) Balanced Equation: 2 H 2 + O 2
2 H 2 O Mole Ratio: 2 : 1 : 2
Slide 8
Homework Text (Avogadros principal): Pg. 581 # 1 4 Read Section
12.4 Gas Mixtures and the law of Partial Pressures (Pg. 592-594)
Explain what is meant by partial pressure using a specific example
State Daltons law of partial pressures and include the formula Read
sample problems 1 & 2 (on pg. 594) and complete practice
problems # 1-4 that follow