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Flashcards in 13.1 and 14 Deck (32):
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3 assumptions in kinetic theory of gases

the particles in a gas are considered to be small, hard spheres with an insignificant volume
the motion of the particles in a gas is rapid, constant, and random
all collisions between particles in a gas are perfectly elastic

1

2 extra points about kinetic theory of gases

random walk
no repulsive or attractive forces

2

3 units of pressure

pascal
atm - standard atmosphere
millimeters of Hg - mm Hg

3

which unit of pressure is SI

kPa

4

what causes pressure

simultaneous collisions of billions of rapidly moving particles in a gas with an object

5

What is STP

standard temperature and pressure
0 degrees C
101.3 kPa
1 atm

6

What is the volume of 1 mole of gas at STP

22.4 L

7

what is the relationship between temperature and average kinetic energy

directly proportional

8

what does it mean when two variables are directly proportional

increase or decrease together

9

what does it mean when two variables are inversely proportional

1 increases while the other decreases

10

why does pressure increase when you increase the number of moles

adding moles increases the number of collisions which results in pressure

11

why does pressure increase when you increase the temperature

the kinetic energy increases and faster-moving particles strike the walls of their container with more energy

12

why does air rush out of an object at high pressure and into an object at low pressure

differential pressure
the air is trying to reach atmospheric pressure

13

what is the combined gas law

P1V1 P2V2
----- = ------
T1 T2

14

what variable can be calculated from the ideal gas law that cannot be calculated by the combined gas law

number of moles

15

What is the ideal gas law

N=PV
---
RT

PV=nRT

16

what is r

ideal gas constant
8.31

17

how to determine R at stp

L*kPa
-------
R*moles

18

what is partial pressure

the contribution each gas in a mixture makes to the total pressure

19

what is compressibility

a measure of how much the volume of matter decreases under pressure

20

what is effusion

a gas escapes through a tiny hole in its container

21

what is diffusion

the tendency of molecules to move toward areas of lower concentration until the concentration is uniform

22

what is the total pressure

the sum of the partial pressures

23

diffusion and effusion rates

gases of lower molar mass do it faster than those with high molar masses

24

the rate of effusion of a gas is _____ compared to a gas's molar mass

inversely proportional to the square root of a gas's molar mass

25

when are real gases most similar to ideal gases

high temperatures and low pressures

26

as pressure increases volume...

decreases

27

as temperature increases volume...

increases

28

as temperature increases, pressure...

increases

29

why are gases compressible

volume of particles is smaller than volume of gas
distance between particles is large

30

what is kinetic energy

the energy an object has because it is moving

31

what is a vacuum

empty space with no particles and no pressure