Ch 14: The Behavior of Gases Flashcards
What are three factors that determine the volume of a gas?
Temperature
Pressure
Amount of gas
Type of relationship: P ∝ 1/V
Inverse
Type of relationship: T ∝ V
Direct
Type of relationship: n ∝ V
Direct
Type of relationship: quantity A goes up, then quantity B goes up.
Direct relationship
Type of relationship: quantity A goes up, then quantity B goes down (and vice-versa).
Inverse relationship
How do we purify mixtures?
With a physical change (boiling, filter, magnet, diffusion, distillation, chromatography).
How do we break apart compounds?
With a chemical change (heat and properties change).
How do we break down elements (into other elements)?
With nuclear change (fission, fusion).
Kind of atoms they hold together: covalent bonds
Nonmetal atoms
Kind of atoms they hold together: ionic bonds
A nonmetal and a metal
Kind of atoms they hold together: metallic bonds
Metal atoms or positively charged ions
How/why do they hold atoms together: covalent bonds
Both holding on to electrons in the covalent bond.
How/why do they hold atoms together: ionic bonds
Attraction between opposite charges.
How/why do they hold atoms together: metallic bonds
Opposite charges between positive metal cation and negative anion electrons.
What is not shared evenly or uneven sharing classified as?
Polar
What is even sharing classified as?
Nonpolar
What are oppositely charged sides of neighboring polar molecules attract each other?
Dipole-dipole
What type of forces are dipole-dipoles?
Intermolecular forces; between molecule
What is an especially strong attraction between neighboring molecules that contain an O-H bond, or an N-H bond, or an H-F bond?
Hydrogen bonding
Because O, N, and F are very electronegative, what is left?
An unprotected proton.
What does salt do to Hydrogen bonds?
Enhances the effect.
What is an electron cloud of a negative molecule that shifts about randomly?
London dispersion forces (van der Waals forces)
When van der Waals forces shift about randomly, an non polar molecule becomes a temporary ______.
dipole
The London dispersion forces shift induces a neighboring molecule to shift its electrons and these charge interactions do what?
Hod the particles together.
Kind of atoms they hold together: dipole-dipole
Polar molecules
Kind of atoms they hold together: London dispersion forces (van der Waals)
Non-polar molecules
Kind of atoms they hold together: Hydrogen bonds
Molecules that contain O-H, N-H, H-F bond.
What is the strongest bond?
Covalent bond
What is the second-strongest bond?
Ionic bond
What is the third-strongest bond?
Metallic bond
What is the fourth-strongest bond?
Hydrogen bond
What is the fifth-strongest force?
Dipole-dipole forces
What is the sixth-strongest force?
London dispersion forces
Why are gases easily compressed?
Because of the space between the particles in a gas.
What is pressure a measure of?
How concentrated a particular force is.
________ = force/area
Pressure
What is the tool used for measuring atmospheric pressure?
Barometer
What is the tool for measuring the pressure of a contained gas?
Manometer
What is an “ocean of air?”
Atmosphere
What has mass and is bearing down us due to accelerations?
Atmosphere
Why is there less atmospheric pressure at higher altitudes?
Because there is less air mass above.
Standard pressure: atmospheres
1 atm
Standard pressure: pascals
101,325 Pa
Standard pressure: kilopascals
101.3 kPa
Standard pressure: millimeters of Mercury
760 mm Hg
Standard pressure: torr
760 torr Hg
Standard pressure: pounds per square inch
14.7 psi
Standard pressure: inches of Mercury
29.9 in
What all affect gas pressure?
Amount of gas
volume
temperature
Why does the pressure increase when more gas is added to a container without changing the volume of the container?
There are more collisions when more gas is added.
What happens when more gas is added to a container without changing the volume of the container?
The pressure increases.
When you increase the temperature of a gas, what does the pressure do?
The pressure increases.
Why does the pressure increase when you increase the temperature of a gas?
The warm temperatures heat the particles and collisions happen more forcefully.
If the temperature is constant, as the pressure of a gas increases, the volume _________.
decreases
If the temperature is ________, as the pressure of a gas increases, the volume decreases.
constant
How does the pressure relate to the volume, of a fixed amount of gas at a constant temperature?
Inversely
What are the manipulated variables in Boyle’s law?
Pressure and volume.
What are the constant variables in Boyle’s law?
Temperature and amount of gas.
P1 X V1 = P2 X V2
Boyle’s law
If the pressure is constant, what happens to the volume as the temperature of an enclosed gas increases?
The volume increases.
What are the manipulated variables in Charles’s law?
Volume and temperature.
What are the constant variables in Charles’s law?
Amount of gas and pressure.
What is the variable relationship in Charles’s law?
Direct
V1 / T1 = V2 / T2
Charles’s law
According to Gay-Lussac’s law, as the temperature of an enclose gas increases, the pressure _________, is the volume is constant.
increases
What are the manipulated variables in Gay-Lussac’s law?
Pressure and temperature.
What are the constant variables in Gay-Lussac’s law?
Volume and amount of gas.
What is the variable relationship in Gay-Lussac’s law?
Direct
P1 / T1 = P2 / T2
Gay-Lussac’s law
What type of calculations does the combined gas law allow you to do?
Calculations for situations in which only the amount of gas is constant.
P1 X V1 / T1 = P2 X V2 / T2
Combined gas law
What states at constant temperature and pressure, the volume of gas is directly related to the number of gas particles?
Avogadro’s law
What are the manipulated variables in Avogadro’s law?
Volume and number of gas particles.
What are the constant variables in Avogadro’s law?
Pressure and temperature.
What is the variable relationship in Avogadro’s law?
Direct
N1 / V1 = N2 / V2
Avogadro’s law
What is required to calculate the number of moles of a contained gas?
An expression that contains the variable n.
When do real gases differ most from an ideal gas?
At low temperatures and high pressures.
In a mixture of gases, the total pressure is the ___ of the partial pressures of the gases.
Sum
P = P1 + P2 + P3 + …
Total pressure is the sum of the partial pressures of the gases.
