What is kinetic molecular theory?
the theory that explains the behavior of gases at the molecular level
What is an ideal gas?
a model that effectively describes the behavior of real gases at conditions close to STP (STANDARD TEMPERATURE AND PRESSURE);
a gas for which the product of the PRESSURE and VOLUME is proportional to the ABSOLUTE TEMPERATURE
What are the 4 parts to the kinetic molecular theory?
1. Ideal gas particles are very small: their volume is essentially zero when compared with the total volume of the gas.
2. They are in constant rapid motion
3. there are NO attractive and repulsive forces; collisions are completely elastic
4. the average kinetic energy is DIRECTLY proportional to the absolute temperature, measured in KELVIN
What does kinetic molecular mean?
movement of molecules.
What assumptions do we make for ideal gas? Is it realistic?
IT IS NOT REALISTIC.
1. no particles can take up zero volume. we assume this.
2. the attractive/repulsive forces are very small, so we disregard them. they begin to matter when the particles come very close together: then they begin to condense.
3. there is no such thing as totally elastic collision: energy is always transferred. However, particles do conserve ALMOST all of their energy.
What are the four variables that describe a gas?
4. Number of molecules.
The temperature of a gas determines what?
the average kinetic energy of the particles
Do all gas particles travel at the same speed?
false. they travel at different speeds.
*****TEMPERATURE FOR GAS MUST BE EXPRESSED IN?*****
If given Celsius, add 273 to get Kelvin.
Also, there is no degree mark for Kelvin. Just "K".
0 in Kelvin represents what?
no molecular motion. absolute zero.
How do you derive the volume of a gas?
What is the formula for volume?
length x width x height
How many cm³ are in one dm³?
1000 cm³ = 1 dm³
What is the formula for pressure?
force divided by area. Ex: The pressure of a gas is the force of its particles exerted over an area.
the force exerted per unit area.
Adding particles, or reducing the space for the particles, results in?
greater pressure; an increase in collisions of the particles.
What is the SI unit of measure for pressure?
What is the pascal equal to?
What is the conversion from mmHg - torr - kPa for 1 atm?
750 mmHg -1 atm.
750 torr - 1 atm.
101.325 kPa - 1 atm.
Are mmHg and torr equal?
yes. they are exactly equal, and they mean the same exact thing.
How do you express the number of molecules?
in moles. If you are given grams, convert.
Gases with equal volumes have ______ numbers of particles.
Define Avogadro's principle.
Equal volumes of different gases under the same conditions have the same number of molecules.
Does Avogadro's principle hold true for ANY two types of gases?
What is molar volume?
the volume of one mole of a substance at STP.
****WHAT IS THE MOLAR VOLUME FOR ANY GAS??!??!***
22.4 L <---- this is very very very important
What is STP (Standard Temperature and Pressure)?
Standard conditions for a gas of:
- 0 degrees Celsius (273 Kelvin)
- 1.0000 atmospheres.
Other examples of STP conditions are:
1. 273 K and 101.325 kPa
2. 273 K and 760.0 mmHg
3. 273 K and 760.0 torr