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Flashcards in Ch 11 Section 1 Deck (55):
1

the pressure increase is caused by the increase in the number of ..... with the inside walls o the tire

collisions of molecules of air

2

the collisions cause an outward... against the inside walls

push, or force

3

gas molecules exert .... on any surface with which they...

pressure; collide

4

the pressure exerted by a gas depends on

volume, temperature, and the number of molecules present

5

pressure is defined as the ..... on a surface

force per unit area

6

Pressure =

force/ area

7

SI unit for force is

newton

8

newton is the force that will increase the speed of a ... by .... each ... that the ...

one-kilogram mass; one meter per second; second; force is applied

9

at earth's surface, gravity has an acceleration of

9.8 m/ s^2

10

The atmosphere exerts

pressure

11

The pressure of the atmosphere can be thought of as caused by the weight of the .... that

gases; compose the atmosphere

12

the atmospheric pressure at sea level is eqaul to the weight of a .... mass per square centimeter of surface

1.03 kg

13

the atmosphere contains about.... nitrogen, .... oxygen, and ... other gases, including...

78%; 21%; 1%; argon and carbon dioxide

14

atmospheric pressure is the sum of the individual pressures of the

various gases in the atmosphere

15

a barometer is a device used to measure

atmospheric pressure

16

first type of barometer was introduced by... during the early ...

Evangelista Torricelli; 1600s

17

the mercury in the tube pushes downward because fo

gravitational for e

18

the column of mercury in the tube s stopped from falling beyond a certain point because the atmosphere exerts a ... on the surface of the mercury outside the tube

pressure

19

this pressure is transmitted through the fluid mercury and is exerted

upward on the column of mercury

20

the mercury in the tube falls only until the pressure exerted by its weight is equal to the ....

pressure exerted by the atmosphere

21

the exact height of the mercury in the tube depends on the

atmospheric pressure, or force per unit area

22

th pressure is measured in terms of the mercur column's ... in the barometer tube

height

23

from experiments like Torricelli's it's known that at sea level and at 0 degrees C the average pressure of the atmosphere can support a

760 mm column of mercury

24

the atmospheric pressure at any given place depends on the

elevation and the weather conditions

25

if the atmospheric pressure is greater than the average at sea level, the height of the mercury column in a barometer will be

greater than 760 mm and vice versa

26

all gases exert

pressure

27

a device called a manometer can be used to measure the pressure of an

enclosed gas sample

28

the difference in the height of mercury in the two arms of the U-tube is a measure of the

oxygen gas presure in the container

29

because atmospheric pressure is often measured by a mercury barometer, pressure can be expressed in terms of the

height of a mercury's column

30

thus, the common unit of pressure is

millimeters of mercury (mm Hg)

31

a pressure of 1 mm Hg is also called

1 torr

32

the average atmospheric pressure at sea level at 0 degrees C is

760 mm HG

33

One atmosphere of pressure is defined as being exactly equivalent to

760 mm Hg

34

In SI, pressure is expressed in derived units called

pascals

35

one pascal is defined as the pressure exerted by a force of one

newton acting on an area of one square meter

36

it's more convenient to express pressure in

kilopascals

37

standard atmosphere is equal to

1.01325 x 10^5 Pa, or 101.326 kPa

38

to compare volumes of gases, one must know the

temperature and pressure at which the volumes are measured

39

for purposes of comparision, scientists have agreed on standard conditions of exactly

1 atm pressure and 0 degrees C

40

1 atm pressure and 0 degrees C are called

standard temperature and pressure

41

the pressure exerted by each gas in an unreactve mixture is independent of that exerted by

other gases present

42

the pressure of each gas in a mixture is called the

partial pressure of that gas

43

dalton's law of partial reassures states that the total pressure of a gas mixture is the sum of the

partial pressures of the component gases

44

dalton's law: Pt=

P1 + P2 + P3

45

each of the rapidly moving particles of gases in a mixture has an equal chance to

collide with the container walls

46

therefore each gas exerts a pressure indepedent of that exerted by the

other gases pressent

47

the total pressure is the result of the total number of collisions per

unit of wall area in a given time

48

gases produced in the lab are ften collected over

water

49

the gas produced by the reaction displaces the water, which is more dense, in the

collection bottle

50

a gas collected by water displacement is not pure but is always mixed with

water vapor

51

that is because water molecules at the liquid surface

evaporate and mix with the gas molecules

52

water vapor like other gases exerts a pressure known as

vapor pressure

53

Patm =

Pgas + PH2O

54

to find the partial pressure of the dry gas collected you would subtract the pressure of the water vapor at the given temperature from the

total pressure

55

the vapor pressure of water varies with

temperature