Ideal Gas Law
The key phrase you want to associate with pressure is
"the number of times particles hit the walls of the container"
Gas is compressed from an initial volume of 12L to 6L. Temperature increases from 400K to 800K. What happens to the other particles?
(PVNT) N - Constant V - reduced by half T - doubled P - Increased by 4 (PK direct relation Gay-Lussac Law as temperature doubled, so did pressure; PV inverse relation Boyles Law as volume reduced by half, pressure increased by 2)
Standard Temperature
0 degrees C° 273.15 K (°C + 273.15 = K)
Standard Pressure
1.00 atm 760 mm Hg 760 torr 101.3 kPa
Standard Temperature and Pressure (STP)
A temperature of 273 K and a pressure of 1.00 atm
Explain Gay-Lussac's Law
As temperature increases, particles move faster causing collisions with the sides of the container to happen moreterm-20 often and to be stronger. This increases the pressure
What happens tp pressure, when another gas is added into a container?
As we know, gas pressure results from the number of collisions that occur between gas particles and the walls of their container. If we add more gas particles to the container, the number of collisions, and thus the pressure, will increase.
V1/n1 = V2/n2
Avogadro's Law equation V stands for volume n stands for moles of gas numbers refer to initial and final conditions
Ideal gas Law breakdown
Boyle - V & 1/p Charles - V & T Avagardo - V & N put it all together V & TN/P (Put P to other side and make constant an equal sign) PV = NRT
A balloon is filled with hot air. Once taken outside on a cold day, the volume decreases by 1/6. What is this relationship.
Charles Law; The relationship of Temperature and Volume (Direct Relation); In this case we know temperature was reduced by 1/6 (since volume reduced by 1/6) so long as P and N are constant.
V1/T1 = V2/T2
Charles law equation V stands for volume T stands for temperature numbers refer to the initial and final conditions
How do we determine the total pressure or individual pressure of one gas in a mixture of gases?
Daltons Law
P1/T1 = P2/T2
Gay-Lussac's Law equation P stands for pressure T stands for temperature numbers refer to initial and final conditions
Boyle's Law
Indicates an inverse relationship between pressure and volume when n and t are constant (PV)
Ideal Gas Law Units
P - atm V - L T - K N - mol
P1V1 = P2V2
P stands for pressure V stands for volume numbers refer to the initial and final pressures and volumes
Ideal Gas Law Formula
PV=nRT P - pressure in atm (or mmHg or torr) V- volume in liters n - number of moles of gas particles in the container R - ideal gas constant T - temperature in Kelvin
Another way to represent Dalton's Law
Px/total pressure = Xa (moles X/total moles) Px represents partial pressure over the total pressure and the fraction on the right is the mole fraction
A gas in a container has a pressure of 6.0 ATM. The container is opened until the pressure is reduced to 3.0 ATM and then closed again. What is this relationship?
The relationship of Number of particles and Pressure (Direct Relation); In this case we know N is reduced by half (since P was reduced by half) so long as T and V remain constant
Why does pressure increase when volume decreases?
This happens because when volume decreases, you are reducing the space of the container which causes the particles to collide with the side of the container more often, thereby increasing pressure (the number of times the particles hit the container)
How do we determine the pressure of one gas (Partial pressure) in a mixture of gases, when given the total pressure?
To do this, we use the mole fraction of that gas
Why does volume increase when temperature increases?
When temperature or average kinetic energy increases, particles move faster causing more and stronger collisions with the walls of the container. The volume in turn increases to keep the pressure constant
Gas Laws & Relationships
a set of laws that describe the relationship between pressure, volume, temperature, and moles of gas - Boyle's Law - Charles' Law - Gay-Lussac's Law - Avogadro's Law - The Combined Gas Law
The following Gas Laws and Relationships hold true only when the amount of gas is _______________________
constant
Ideal Gas Law
describes the behavior of an ideal gas or describes the variables that effect gas behavior
Avogadro's Law
direct relationship between the # of moles and volume (NV)
What's the relationship between Pressure and Number of particles?
directly related; as the number of particles increases, so does the pressure when all else is constant
The higher the temperature of a substance, the ____________________ the average kinetic energy
greater
Charles' Law
indicates that there is a direct relationship between Volume and Temperature (TV)
Volume and Pressure are ___________________ related which means .....
inversely; as pressure increases, volume decreases and as volume increases, pressure decreases
Mole Fraction (Xa)
moles of A/total moles for example, if we have a mixture of 3 mol O2 and 4 mol H2, the mole fraction of O2 = 3/(3+4) = 3/7
After finding the mole fraction, how do we determine the partial pressure of said gas?
multiply the mole fraction by the total pressure 3/7 X 7
Ideal Gas Law Constant
relates to the other four variables together and depends on the units used for pressure and volume. R = 0.0821 L•atm/mol•K when P is atm, V is L R = 8.31 J/mol•K when P is kPa, V is dm3
Why does volume increase, as number of particles increase?
same reasoning as charles law; Adding more particles to a container causes more collisions with the walls of the container and the volume increases to keep the pressure constant
Dalton's Law of Partial Pressures
states that the total pressure of a mixture of gases is equal to the sum of the pressures of all the gases in the mixture Ptotal = P1 + P2 + P3... total pressure is equal to pressure of gas 1, plus pressure of gas 2, plus....
Gay-Lussac's Law
the Pressure of a gas is directly proportional to the Kelvin temperature if the volume is constant (PK)
Temperature (T)
the average kinetic energy of gas particles measured in Kelvin
Pressure (P)
the force that gas particles exert on the interior surface of the container through collisions
Moles (N)
the number of moles of gas
Volume (V)
the region of space the gas occupies