Flashcards in Ch 11 Section 2 Deck (58):

1

## Robert Boyle discovered that gas pressure and volume are

### related mathematically

2

## the observations of Boyle and others led to the development of the

### gas laws

3

## the gas laws are simple mathematical relationships between the

### volume, temperature, pressure, and amount of a gas

4

## Robert Boyle discovered that doubling the pressure on a sample of gas at constant temperature reduces its

### volume by one-half

5

## reducing the pressure on a gas by one-half allows the volume of the gas to

### double

6

## the pressure of a gas is caused by moving molecules hitting the

### container walls

7

## if volume of container is decreased but same number of gas molecules is present at the same temperature then there will be more molecules per

### unit volume

8

## the number of collisions with a given unit of wall area per unit time will .... and therefore...

### increase as a result; pressure will also increase

9

## plotting values of volume versus pressure for a gas at constant temperature gives a

### curve

10

## the general-volume pressure relationship illustrated is called

### boyle's law

11

## boyle's law states that the volume of a fixed mass of gas varies inversely with the pressure at

### constant temperature

12

## Boyle's la can be expressed as : PV=

### k

13

## P is

### pressure

14

## V is

### volume

15

## k is a

### constant

16

## Since P and V vary inversely, their product remains the

### same

17

## because two quantities that are equal to the same thing are equal to each other, the relationship between changes of pressure and volume can be expressed as: P1V1 =

### P2V2

18

## P1 and V1 are

### initial conditions

19

## P2 and P2 are a

### different set of conditions

20

## given three of the four values P1, V1, P2, and V2, you can use this equation to calculate the fourth value for a

### system at constant temperature

21

## if pressure is constant, gases expand when

### heated

22

## when temperature increases, the volume of a fixed number of gas molecules must increase if the pressure is to

### stay constant

23

## at the higher temperature, the gas molecules move

### faster

24

## they collide with the walls of the container more frequently and with more

### force

25

## the volume of a flexible container must then increase in order for the pressure to

### remain the same

26

## the quantitative relationship between volume and temperature was discovered by the French scientist

### Jacques charles in 1787

27

## Charles's experiments showed that all gases expand to the same extent when heated through the

### same temperature interval

28

## charles found that the volume changes by 1/273 of the original volume for each

### celsius degree, at constant pressure and initial temp of 0 degrees celsius

29

## the same regularity of volume change occurs if a gas is cooled at

### constant pressure

30

## the kelvin temperature scale is a scale that starts at a temperature corresponding to

### -273.15 degrees celsius

31

## -273.15 degrees celsius is the lowest one

### possible

32

## the temperature -273.15 degrees celsius is referred to as absolute zero and is given a value of

### zero in the Kelvin scale

33

## K =

### 273.15 + degrees C

34

## gas volume and kelvin temperature are

### directly proportional to each other at constant pressure

35

## charles's law states that the volume of a fixed mass of gas at constant pressure varies directly with the

### Kelvin temperature

36

##
charles's law:

V =

k=

###
V = kT

V/T= k

37

## the value of T is the

### kelvin temperature

38

## The ratio V/T for any set of volume-temperature values always equals the same

### k

39

## the form of charles's law that can be applied directly to most volume temperature problems involving gases is:

### V1/ T1 = V2/ T2

40

## V1 and T1 represent

### initial conditions

41

## V2 and T2 represent a

### different set of conditions

42

## when 3 of the 4 values T1, V1, T2, and V2 are known, the equation can be used to calculate the fourth value for a

### system at constant pressure

43

## the energy and frequency of collisions depend on the average

### kinetic energy of molecules

44

## for a fixed quantity of gas at constant volume, the pressure should be directly proportional to the

### Kelvin temperature, which depends directly on average kinetic energy

45

## for every kelvin of temperature change, the pressure of a confined gas changes by

### 1/273 of the pressure at 0 degrees C

46

## Gay-Lussac's law: the pressure of a fixed mass of gas at constant volume varies

### directly with the Kelvin temperature

47

##
Gay-Lussac's law is expressed as :

P =

k=

###
P = kT

P/T= k

48

## in gay lussac's law k is constant that depends on the

### quantity of gas and volume

49

## for given mass of gas at constant volume, the ratio P/T is the same for any set of

### pressure-temperature values

50

##
unknown values can be found using the following form of gay-lussac's law:

### P1/ T1 = P2/ T2

51

## a gas sample often undergoes changes in temperature, pressure, and volume all at the

### same time

52

## the combined law expresses the relationship between

### pressure, volume, and temperature of a fixed amount of gas

53

## combined gas law: k=

### PV/ T

54

## in combined gas law, k depends on the

### amount of gas

55

## combined gas law can also be written as:

### P1V1/ T1 = P2V2/ T2

56

## each of the gas laws can be obtained from the combined gas law when the

### proper variable is constant

57

## boyle's law is obtained from the combined gas law when

### temperature is constant

58