Chapter 10: Gas Laws Flashcards
What is KMT based on?
The concepts that all particles of matter are in constant motion how particles move
What does KMT explain?
The properties of solids, liquids and gases in terms of their kinetic energy ad the forces which act upon them
According to KMT, what are gases made of?
Large number of tiny particles that are far apart, relative to their size
”” what motion are gas particles in? 3
Constant rapid and random motion
”” how do gas interact with eachother?
Gas particles do not attract or repel each other they Only collide and bounce off each other.
”” what does the KE of gas molecules depend on?
On their Temperature. Hot gases move faster, cold slower
What do gas particles collide with?
Eachother and the walls of their containers, experiencing “elastic collision”
Define elastic collisions
Collision in which there is no less of KE. The NRG lost by the striking particles is Gaines entirely by the particle that is hit or by the wall of the container holding the gas
Describe the shape and volume of gas
Gases have no shape or volume. They take shape and volume of whatever container they are in
Why do gases take on shape and volume of their container,
Because they have no shape or volume
Why do gases flow?
There attractive forces between the particles are insignificant
Why do liquids flow?
Their attractive forces are weak
Why don’t solids flow?
Their attractive forces are strong
Compare the density of gases to liquids and solids
Density of solids and liquids are 1000 tomes more dense than gas
Why can gases be compressed?
Their particles are far apart
Why can we fit a lot of gas in a small container ?
Because their particles are far apart and compressing them I my forces them together closer
Define deffusion
The mixing of gases caused by their random motion
When is diffusion faster? 2
At high Temp. And with smaller particles
Define effusion
The escape if a gas under high P through a small opening
Define ideal gas
An imaginary gas that conforms to all assumptions of KMT
Define a real gas
One that doesn’t conform to KMT
When is the behavior of a real gas especially noticeable ? 2
Very high temperature and very low temperature
Define pressure
Force per unit area on a surface
Name the 4 units of pressure, abbreviations and standard values
1 ATM 760 mm Hg 101.325 ( Kilopascals) kPa 760 (Torricelli) Torrs
What is STP
Standard temperature and pressure
What is STP equal to
0 degrees Celsius or 273 K
What is STP used for
Comparison between/among gases
State Boyles law
A volume of gases varies inversely with its pressure IFF Temperature is constant
What is the formula for Boyles law and define the variables
PV=P’V’ P is the original pressure on a volume of gas and P’ is changed pressure and V is a volume of gas and V’ is a changed volume resulting from a change in pressure
When does Boyles law not hold true
Very high pressures
Why doesn’t Boyles law hold true?
In Theory if the pressure was high enough Volume could equal 0
Why was the Kelvin temperature scale developed?
To avoid negative numbers in calculations
What is the value of absolute zero in degrees Celsius?
-273
What happens to matter at Absolute zero?
It becomes so cold it can’t really be attained
How do you convert Celsius to Kelvin
Add 273 to the measured temperature in degrees Celsius
State Charles law
The volume of a gas varies directly with the Kelvin temperature IFF P is constant
State the formula and define the variables for Charles law
V/T=V’/T’
Where V and T are the originals an V’ and T’ are the changed
When does Charles law not hold true?
Very low temperatures
Why does Charles law not good true at very low temperatures?
In theory as temperature decreases to a certain point V could be zero
State Gay-Lussacs law
The pressure exerted by a gas varies directly with Kelvin IFF V is constant
State the formula and define the variables for gay Lussacs law
P/T=P’/T’
Where P and T are originals and the others are changed
What is the formula for combine gas laws and define the variables
V’/V= P/P’xT’/T
Exists cause V P T all change at the same time
What did Dalton study?
Mixtures of gases
What is partial pressure?
The pressure exerted by each force in a mixture
State Daltans law
The total pressure exerted by a mix of gases is equal to the sum of the partial pressure if each gas in the mixture
What is the formula and define variables for Daltans law
P(total)= PP(gas1) + PP(gas2)….
How do you recognize a Daltans correction?
By water displacement or over water
Explain the partial pressure of water vapor
Some water vapors enter the bubbles as they pass through the water
How do you correct the collection pressure?
PP of water must be subtracted from the collection pressure for accurate results
