The Gas Phase

Question 1

STP v. Standard condtions

Answer 1

273 K v. 298 K

Question 2

How does a real gas deviate from an ideal gas?

Answer 2

At high pressures
Low volumes
Low temperatures

Question 3

What is an ideal gas?

Answer 3

No intermolecular interactions, no volume

Question 4

Avogadro’s principle

Answer 4

All gases at a constant temperature and pressure occupy volumes that are directly proportional to the number of moles of gas present

Question 5

Different systems of pressure measurement

Answer 5

1 atm=760 mmHg = 760 torr = 101.325 kPa

Question 6

As the number of mols of gas increases?

Answer 6

The volume increases in direct proportion

Question 7

Boyle’s Law

Answer 7

For a given gaseous sample at a constant temperature, the volume of gas is inversely proportional to pressure

Question 8

Charles’s Law

Answer 8

At constant pressure, volume of gas is proportional to its absolute temperature

Question 9

Gay-Lussac’s Law

Answer 9

At constant volume, pressure and temperature are proportional

Question 10

Dalton’s Law of Partial Pressures

Answer 10

When to or more gases that do not chemically interact are found in one vessel, each gas will behave independently of the others
Pressure exerted by one gas will equal pressure if only one gas was in the container

Question 11

Henry’s Law

Answer 11

Vapor pressure is pressure exerted by evaporated particles above the surface of a liquid
Solubility of gas increases with increasing partial pressure

Question 12

Kinetic molecular theory

Answer 12

Explains behavior of gas
Assumes:
1.) Gases have negligible volumes
2.)No intermolecular attractions or repulsions
3.)In continuous, random motion undergoin collisions
4.)Collisions are elastic (momentum and kinetic energy conserved)
5.)Average kinetic energy of gas is proportional to absolute temperature of gas and is the same for all gases at a given temperature

Question 13

How are the speeds of gases defined?

Answer 13

in terms of average molecular speed

Question 14

What does kinetic energy of a gas particle depend on?

Answer 14

Temperature

Question 15

Larger molecules move

Answer 15

Slower

Question 16

Molecules with higher molecular weights diffuse?

Answer 16

Slower

Question 17

Graham’s Law

Answer 17

Under isothermal and isobaric conditions, rates at which two gases diffuse and effuse are inversely proportional to square roots of their molar masses

Question 18

Effusion

Answer 18

Flow of gas particles under pressure from one compartment to another through a small opening

Question 19

When does gases deviate from ideal the most?

Answer 19

At low temperature
High pressure
Low volume

Question 20

When does gases most act like ideal gases?

Answer 20

High temperature
Low pressure
High volume

Question 21

At moderately high pressure, what happens to gas volume?

Answer 21

Less

Question 22

At extremely high pressure, what happens to gas volume?

Answer 22

Size of particles become large compared to distance between them and volume increases

Question 23

As temperature of gas is reduced toward its condensation point, what happens to volume?

Answer 23

It decreases

Question 24

At extremely low temperature, what happens to volume?

Answer 24

It increases