Amount Of Substance - Ideal Gases Flashcards
What is Avogadro’s Hypothesis on gases?
1 mole of any gas would fill the same volume of space
Avogadro’s Hypothesis
What is the volume of space?
24,000cm*3
Avogadro’s Hypothesis
When would this occur?
Measured at room temperature and pressure
Avogadro’s Hypothesis
What is the molar gas volume?
The volume per mol of gas molecules
Avogadro’s Hypothesis
What is the molar gas volume at room temperature and pressure?
Approximately 24 dm3 mol-1
1 mol = 24,000 cm*3
What is 24,000 cm3 in dm3?
24 dm*3
If 1 mol is 24 dm*3, what is
0.5 mol
2 mol
0.5 mol = 12 dm*3
2 mol = 48 dm*3
What is the calculation triangle for
volume of gas (V)
Number of moles (n)
Molar gas volume (24)
V
——————
n | 24
What does volume of gas =
Number of moles x molar gas volume
What does number of moles =
Volume of gas / molar gas volume
What does molar gas volume =
Volume of gas / number of moles
What are the units for volume of gas?
dm*3
What are the units for number of moles?
Mol
What are the units for molar gas volume?
dm3 mol-1
What is the ‘ideal’ behaviour of gasses?
5
Molecules act as though they are ridged spheres
Molecules are in constant motion
Molecules exert a constant pressure on the walls of their container
Collisions of molecules are completely elastic
As temp increases, kinetic energy of molecules increases
What are the key assumptions we make of gases?
2
Any intermolecular forces between gas molecules is entirely negligible
Relative to the volume of their container, the volume occupied by the molecules themselves in negligible
What is the ideal gas equation?
Words
Pressure x volume = number of moles x gas constant x temp
What is the ideal gas equation?
Symbols
pV = nRT
What is the unit for pressure?
Pa
What is the unit for volume?
m*3
What is the unit for number of moles?
Mol
What is the unit for temperature?
K
1kpa = ?pa
1,000
1cm3 = ?m3
0.0001
How do we change a °c into °Kelvin?
Add 273
